#343 – The evolving role of radiation: advancements in cancer treatment, emerging low-dose treatments for arthritis, tendonitis, and injuries, and addressing misconceptions | Sanjay Mehta, M.D.
Episode Stats
Length
2 hours and 12 minutes
Words per Minute
215.17786
Summary
Dr. Sanjay Mehta is a radiation oncologist at St. Joseph's Medical Center in Houston, Texas, where he has been in practice for more than 20 years. In this episode, we discuss the history and misconceptions of radiation exposure, including radiation exposure in modern medicine, including radiophobia, nuclear accidents, and early uses of radiation. We also discuss the role of low-dose radiation for inflammatory conditions such as arthritis and tendonitis, and why this approach is more widely used outside of the U.S. than it is in the United States.
Transcript
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Hey, everyone. Welcome to the Drive podcast. I'm your host, Peter Atiyah. This podcast,
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my website, and my weekly newsletter all focus on the goal of translating the science of longevity
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of the subscription. If you want to learn more about the benefits of our premium membership,
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head over to peteratiyahmd.com forward slash subscribe. My guest this week is Dr. Sanjay
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Mehta. Sanjay is a radiation oncologist at St. Joseph's Medical Center in Houston, Texas,
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where he's been in practice for more than 20 years. I wanted to have Sanjay on the podcast to
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talk about all things pertaining to radiation oncology, but also the history and some of the
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misconceptions around radiation exposure and radiophobia. We talk about some of the very
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interesting applications that I only learned about recently that are very common outside of
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the United States that involve low-dose radiation to treat inflammatory conditions and athletic
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injuries. Now, of course, those of you who are interested may recall that because this podcast
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is called The Drive, I do occasionally talk about cars, and given that Sanjay and I have a shared
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passion for them, and in fact, that's how Sanjay and I met, we do end this discussion with a little
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bit of a deep dive into cars. But of course, back to the main point of this discussion, we talk about
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the evolution of breast cancer, including the shift from radical mastectomies to more conservative
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approaches like lumpectomies and sentinel node biopsies. We talk more broadly about the role that
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radiation plays in modern oncology, how doses have changed, and how advancements in targeting tumors
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while minimizing damage to surrounding tissues have rendered side effects much more rare.
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Certainly more rare than they were even 20 to 25 years ago. Sanjay talks about the role of low-dose
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radiation for inflammatory conditions such as arthritis and tendonitis, and how this approach
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is more widely used outside of the U.S., and why it's his hope and mine that it becomes more adopted
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here in the U.S. We speak about the history and misconceptions of radiation exposure, including
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radiophobia, nuclear accidents, and early uses of radiation. So, without further delay,
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please enjoy my conversation with Dr. Sanjay Mehta.
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I think this is the first time we're together not driving, right?
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I don't know. Somehow we're going to resist the urge for most of this discussion to not talk about
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So, I feel like we will reserve the right to have some automotive discussions at the end. For listeners,
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Sanjay might be one of the most knowledgeable human beings on cars. He's also a very dangerous friend to
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have because he's always the bad one on the shoulder when you're contemplating a new set of wheels or a new
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something for your cars. But in his other life, in addition to being the founder of MD Motorheads,
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Which is a Facebook group of doctors who are gearheads.
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We're about to crack 3,000 members. It's exploded.
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That's awesome. So, shout out to MD Motorheads. You're also a radiation oncologist,
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I guess we thought it would be a really fun idea to do a podcast for a couple of reasons.
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One is just the bread and butter of what you do as a radiation oncologist is a bit of a black box to
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many people. Myself included, if I'm going to be completely truthful, even training in surgical
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oncology, I feel like I had much more familiarity with the medical side of oncology than I did with
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the radiation side of oncology. So, for myself, for the audience, I think it would be wonderful to
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understand more as it's a field that has evolved a lot. I'm guessing the last 25 years has seen a
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It's one of the youngest fields too in that respect. It's not steeped in some of the traditions that
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surgery and medicine are. So, yeah, it's a new field, highly evolving very rapidly. And the
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technology has changed so much just in really in the last decade or two. It's pretty incredible.
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Just out of curiosity, when did it become its own discipline, its own set of boards and everything
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As a kid growing up in Houston, some of my family friends were radiologists. And I remember it just
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like probably an elementary school kid that some of them were talking about radiotherapy. And
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these were diagnostic radiologists who at the time, CT scanning was pretty new in the 80s.
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And prior to that in the 70s, and then prior to that, it was kind of just a fellowship.
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Radiologists would have a Cobalt-60 machine that they would train on for a few weeks. And you do
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a few easy calculations and you do some crude treatments. But it really started, it came into
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its own starting in the 70s and then really more into the 80s. And that's when it became its own
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discipline. And the ACR had a separate carve out. And so, our residency training is completely
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independent of diagnostics now. So, we just do, it's an intern year followed by four years of
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radiation oncology with a little bit of overlap, but not a lot of diagnostic training at all,
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just because there's so much to do just on the therapeutic side.
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Got it. I had no idea that it was that new. And in terms of medicine, that's obviously like
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very new. The second thing that I wanted to talk about on the radiation front is this idea of using
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very low-dose radiation to heal injuries. I think that while people will be incredibly interested
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to understand the ins and outs of radiation oncology, again, given the ubiquity of it in
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treating people, I think a lot of people are going to be very interested in this idea that
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why aren't we using low-dose radiation more to heal some of these nagging orthopedic injuries that
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people have? And of course, we'll go far down the rabbit hole on that. But I don't think we can have
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this discussion without giving people some understanding of what radiation is. And I would like us to do it in
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a way that's both rigorous enough that we can really get into some of the science of this,
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but also get into it gently enough that people that maybe don't remember high school physics well
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enough can come along for the ride and not get lost. But once we get into grays and millisieverts
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and all that stuff, I want everyone to be fluent when we start talking about doses.
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Right, right, right. Radiation itself, the term itself has got a bit of a negative connotation,
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but basically it's part of the electromagnetic spectrum. So we have everything on the one in
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the range of increasing energy of photons, which are just particles of light. On the one end,
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you have radio waves and microwaves. On the other end, you've got infrared, excuse me, you've got
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ultraviolet, and then you get into x-rays and radio waves. And in the middle of all that is the
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visible spectrum. So when you see, I'm sure everyone's seen the graphs where you've got the
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rainbow, red, green, blue that we can see. The human eye can only perceive a tiny little narrow spectrum.
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These are actually wavelengths and energies, which are the very low end energies. You have
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things like radio waves. In that situation, both radio waves and microwaves are what they call
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non-ionizing. And I know you've talked about this on some of your previous podcasts, and you had a
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really good one with Atari Walla from Pronuvo. It was really nice in-depth discussion. But essentially,
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the bottom line is that the low energy stuff that is non-ionizing cannot damage tissue. And that goes
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all the way up to visible light. Then when you start going to the higher energy x-rays, that's
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when you get both x-rays as well as ultraviolet light, and then the higher particle stuff. But
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basically, the higher you go in the energy and the energetics of the particles, the more likely
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exposure to these packets of energy are going to cause damage to your DNA.
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Why is it that the shorter the wavelength, because that's what's changing as you go from radio waves to
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microwaves to visible waves to ultraviolet? Why is it that as the wavelength gets shorter,
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Yeah, I'm not sure what the reason is. They are inversely proportional to each other. I don't
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know that, I guess I'm probably not enough of a physicist to answer that question precisely. But
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having said that, that is the characteristic of this. And in doing so, that's one of the big reasons
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why all the fallacies about your cell phone giving you brain cancer and all are just that. They're
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fallacies because even having a cell phone on your ear for hours a day, it's non-ionizing radiation.
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And standing too close to a microwave oven, again, non-ionizing radiation, so that cannot damage
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The microwave is too long. It doesn't have the energy. You can stand on it all you want. It can
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Correct. It can excite the molecules, but it won't actually eject an electron, which is what would cause
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an ion to form, which is why it's called ionizing. And that's where we deal with on the, I'm on the
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therapeutic end. So diagnostic radiologists deal with lower energy x-rays than we do. The very high
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energy x is what we use in our linear accelerators to treat cancer. So that's the big difference there
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is kilovoltage versus megavoltage, but all of these are ionizing.
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Okay. So let's talk about how these are measured. How do we quantify them? Because people on the podcast
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have heard me talk about this, I suspect. We talk a lot about calcium scores and CT angiograms
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and PET-CT. I think the frequent listener will have been somewhat familiar with how we talk about
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So radiation dosage, there's a couple of different terms that we've talked about. The main one we talk
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about when we're talking about patient treatment is the unit called the GRAE, and that's an SI unit
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that essentially is joules of energy per kilogram of tissue. So that's what they call absorbed dose.
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So that's in tissue. Whereas when you're talking about exposure in the general, in the air, and
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in general exposure, it's in the air, we usually use the term sievert for that. And actually both
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those terms for the most part are equivalent. It's just that the sievert itself will take into
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account if you have different types of x-rays, different qualities of x-rays that have different
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degrees of potential to be ionizing, that they have a quality factor you'll multiply it by.
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But for the most part, we use the term GRAE when we're talking about, for example,
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when I treat a prostate patient, they're going to get somewhere between 70 and 80 GRAE,
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but it's fractionated into small daily doses as to be tolerable for the body.
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And then when we talk about millisieverts like we're going to, that's really just
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a measure of exposure, not absorbed dose in tissue per se.
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What's the relationship between a GRAE and a millisievert? Is it a one-to-one relationship?
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Yeah, so a GRAE and a sievert technically. If anyone's kind of old school, you listen to older
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stuff, you'll hear the term RADs. A lot of people have heard of RADs.
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So one RAD is equal to one centigrade. 100 RADs is a GRAE. It's just an SI unit versus the old
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terminology. And a sievert is the equivalent, only it's in air, not in tissue.
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So when you give 70 GRAE, you're giving 70 sieverts or 70,000 millisieverts over the course
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Okay. Just so people can kind of anchor this to things that are familiar, living at sea level
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exposes us to one to two millisieverts of ionizing radiation a year?
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That's exactly right. At altitude, it could be double that, actually.
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That's right. If you live in Denver, it's easily double that or triple that, correct?
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Just another thing for comparison, a pilot who spends a lot of time traversing the North Pole,
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which is typically how they're going to fly. They're not going to go all the way around the
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center of the earth. Might get another three or four millisieverts of radiation.
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It's quite a bit. Quite a bit. That's right. Per trip, actually. So that can add up.
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And I was actually talking to a pilot friend about this. They don't really have any limitation in terms
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of total exposure that requires them to be taken out of the air. A lot of them, they're forced to
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retire at 65, I think is the commercial requirement. But they don't really monitor the actual
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exposure to that level. And I think the reason they don't really use that as a limiting factor
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for the amount of work is really just that even though they get a higher dose, there's been no
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proven increase in cancer in those types of populations, even in flight attendants or anything
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like that. The same way that people in Denver and the people here in Texas don't have any higher
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incidence of cancer. Now, the NRC recommends that a person not be exposed to more than 50,
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I believe 50 millisieverts of radiation in a year. Correct.
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Now, someone like me, that's easy unless I'm out there getting a lot of diagnostic radiology or,
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of course, undergoing therapeutic radiation treatment. But for someone like you who has
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to set patients up or one of your techs, are you guys approaching that level of exposure?
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Not at all. And so it depends on what type of radiation we do. Now, typically for our external
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beam machines, we're doing it all remotely from behind a shielded wall. So the vault in which
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the machine is placed is custom built just to shield based on the angles that the machine can
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move through. If there's like a direct angle where the machine is hitting a wall, that wall has to be
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built 10 times thicker than the walls where the beam can't reach. So essentially our dose when treating
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remotely is close to zero. So we keep film badges, but it's almost become kind of a joke that when
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we're not doing brachytherapy, which is dealing with actual live radioactive sources, our exposure
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is super low, almost negligible really. But back when I was in residency doing a lot of GYN implants
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and things like that, where you're putting cesium or iridium actually into the body cavities and
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you're actually up there putting it in up close. We had a ring badge on it. As a residence, we'd
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rotate every month, but if we didn't rotate, some of the faculty actually got pretty high doses.
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I know of a couple of folks, the ones who did a lot of GYN therapy, especially in the older
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days, we're talking about in the eighties and the seventies, where you could actually
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see dermatitis on their hands from doing that, just from the hand exposure. One of my faculty
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members actually had a giant cell tumor of the bone in her finger. And again, this is
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after decades and decades of doing it. It was a benign growth, but that was a real thing.
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There's a lot of data out there on, especially people who were dealing in x-ray for dentistry
00:14:02.600
and stuff like that back in the day when they didn't have shielding or anything like that,
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that they would get dermatitis. The most common thing you'd see is skin irritation in that
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sort of situation. Dermatitis and even some chronic flaking and things like that.
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So let's talk about some types of x-rays that people are familiar with and give a sense of
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radiation dose. And I'm also curious as to how much this depends on the size of the individual.
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In other words, does a person that is larger receive more radiation for this same test,
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They certainly do because you have to use more energy to get into a larger person. Having said that,
00:14:38.260
there's two different things here. Because what we normally deal with when I'm talking about dose
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to a tumor is the dose actually at that spot versus a whole body dose, which is a very different
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metric. And so for someone who I'm treating with, say, eight weeks of radiation for prostate cancer,
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their prostate may get 80 gray in 1.8 to 2 gray fractions per day. But that's literally only
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to a small volume, roughly the size of the prostate gland itself. And when you even get just a few
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millimeters away from that, that dose gets cut in half. And then it's exponentially lower
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because the intensity of the radiation varies with the square of the distance.
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So as you get even a couple of feet away, that goes down significantly. But typically a patient who
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is getting 80 grays, if 80 gray was a whole body dose, that would obviously be lethal. But the whole
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body dose is more like a few milligray in that sort of situation. So we typically don't see full body
00:15:32.200
sequelae or anything from doing even the heavy duty diagnostic treatment. Now for the CT scan,
00:15:37.120
we almost consider that negligible in our area. Because again, I'm dealing with
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mega voltage, high dose cancer killing radiation. And so when they get a CT scan, which is going to be
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just a few millisieverts or milligray, that's almost considered rounding error versus what they're
00:15:52.660
But let's take something like a chest x-ray. So chest x-ray, people should anchor to this idea for
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what it's worth. And we can come back to this. NRC says, hey, limit your annual radiation to 50
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millisieverts. You've got 2% of that just being alive because you happen to go outside and be
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exposed to the sun. So the other 98% might come through flying diagnostic. Let's say you fly a lot,
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that might get you up another 10%. So let's talk about a chest x-ray. You got a cough, you go to
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your doctor, they do a chest x-ray. That's how many millisieverts for a normal size person?
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Normal size person, it's a fraction. It's probably less than one millisievert actually. So it's
00:16:32.080
significantly, it's something that where people who are concerned about things like diagnostic
00:16:36.300
mammograms and all every year, you're still talking about maybe one millisievert, even a
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little bit less than that with some of the newer machines. You're in a zone where there's a principle
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we talk about, it's called ALARA, A-L-A-R-A, which is as low as reasonably achievable. And that's been
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the mantra for our radiation safety people, the Nuclear Regulatory Commission and whatnot,
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that you want to keep things as low as possible. But having said that, when you're talking about
00:17:00.700
numbers of less than 50 millisieverts, that's kind of an arbitrary number. I should have maybe
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gotten a chest x-ray when I had my cough last time, but I just don't want to do it. I don't
00:17:08.480
want the exposure. But it's so minimal in terms of biologic effect that we really don't even really
00:17:12.940
worry about those, even if it's getting one of them a month or so. And a big reason for that is
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a lot of these numbers, especially the 50 millisievert number, is extrapolated from higher
00:17:23.260
exposure rates. There's something called the Linear No Threshold Model, or LNT, and that's
00:17:28.660
been written about extensively. And that's what we're all taught in radiobiology and residency.
00:17:33.340
One-fourth of my radiation training in residency was actually radiation biology, in addition to
00:17:38.400
clinical oncology and radiation physics. So the Linear No Threshold Model is what states that
00:17:43.420
we know based on all the data from nuclear fallout from Chernobyl, from Three Mile Island,
00:17:49.520
of course, from Hiroshima and Nagasaki, from the bombs, that at a certain dose exposure,
00:17:53.700
there's a certain risk of developing a cancer or any other endpoint, whether it be dermatitis
00:17:57.960
or bone marrow suppression. All of these numbers are well sorted. But when you try to extrapolate
00:18:02.460
lower, so you take maybe say a dose of one full sievert, the 1,000 millisievert, and you start
00:18:08.440
extrapolating that lower and lower to where you're looking at 100 or 50 millisieverts,
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the Linear Model assumes that there's some level of damage even at those lower levels.
00:18:17.300
But in reality, there's actually a threshold. The LNT, which is Linear No Threshold, has actually
00:18:22.080
been proven to be actually erroneous. And so at very low doses, it's actually been shown that there's
00:18:27.560
almost no incidence of any sort of biological damage. And there's also, it's controversial,
00:18:33.320
but there's animal studies showing there may be a hormesis effect at low, low doses like that.
00:18:37.580
Tell people what that means, because that's obviously going to come back later in our discussion.
00:18:41.180
Regular listeners of your podcast know all about hormesis, and you talk about in the exercise
00:18:45.940
realm and cold plunges and saunas and whatnot. But the whole idea is doing some degree a small
00:18:51.720
amount of cellular damage. When the body repairs that, it actually comes back stronger than it was
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without the exposure in the first place. And in animal studies, they've actually shown at very low
00:19:01.620
doses, we're talking about single-digit millisieverts here, that they've seen in mouse bones,
00:19:06.320
for example, decreased osteoclasts and increased osteoblastic activity. So the bones actually
00:19:10.500
heal quicker. Some of the soft tissue as well has been shown to actually recuperate much in the way
00:19:16.620
you see in the hormesis from other causes. And that's not something that we're claiming is widely
00:19:21.700
accepted, but there is a lot of data showing that that is certainly a possibility, which goes against
00:19:26.200
this classic LNT model. And the LNT model itself, the guy that won the Nobel Prize for it in the
00:19:31.960
1940s, did this all on fruit flies. And his work was disproven over the years after that. And so
00:19:37.500
a lot of this low-dose radiation safety stuff we have is certainly a noble goal to keep the dose as
00:19:43.040
low as possible. But when we get down into these millisievert ranges, I think that they're probably
00:19:46.700
a little bit overblown in terms of the actual negative effects on the human body.
00:19:51.940
When I think about where, for example, something like a CT angiogram used to be,
00:19:56.300
that would easily have exposed a person to 25 millisieverts to do a CT scan of the heart.
00:20:03.200
You're doing it, slowing the heart down, getting the contrast in there, et cetera.
00:20:07.340
Today, the really fast scanners, the best of the best scanners are somewhere between one and three
00:20:13.180
millisieverts for that same procedure. I certainly favor having patients getting a scan with that.
00:20:20.340
Acknowledging, though, that I don't have amazing data to point to, to say that the 25 millisievert
00:20:27.280
one versus, just to make the math easy, the 2.5 millisievert one, 10-fold difference,
00:20:35.540
How do you think about that? What would be your confidence in saying that 2.5 is not actually
00:20:44.680
So again, going back to that Alara principle, there's not a whole lot of data at these levels.
00:20:48.740
I certainly would strive to keep it as low as possible, which is what that mantra says,
00:20:53.280
but I would go with the machine that has the best resolution. And if 25 is,
00:20:57.220
if the radiologist tells me that that image is significantly better than a 2.5
00:21:01.180
millisievert exposure, some of the older machines are just less efficient. You may get a better image
00:21:06.620
with the lower dose. I think the dose is pretty negligible.
00:21:09.220
Got it. So in other words, you're saying, I don't really care if it's 25 or 2.5 is quality.
00:21:12.760
And the good news is these brand new scanners are faster, which is why they're giving you less
00:21:21.700
And the same thing applies. That's on the diagnostic side. On the therapeutic side,
00:21:24.780
where I am, our machines are called linear accelerators. And there's a similar progression
00:21:28.960
as we've been able to focus the beams more and more precisely. It's a modulation of the beam,
00:21:33.920
meaning you have a lot of photons being showered in the general vicinity of a patient,
00:21:38.160
but you're blocking out everything except for a small area to treat. And the same way,
00:21:41.840
the newer machines do definitely have a lower exposure to the, at least in the room in general.
00:21:47.000
So what should people be thinking about in terms of extraneous radiation? When should people be
00:21:54.320
saying to their doctors, hey, do I really need this? For example, when you go to the dentist every
00:21:59.620
year, they typically want to do a set of x-rays. Is that anything people should be worried about?
00:22:03.300
Not at all. Not in the least. I would certainly not skimp on dental x-rays, mammograms, if it's
00:22:09.360
someone that needs cardiac workups and things like that. The risk-benefit ratio is so heavily
00:22:14.040
in favor of doing these studies that I don't even think twice about them. I think part of this comes
00:22:19.240
from, you know, I've been doing this 25 years now. I have so many patients, by the time they come to me
00:22:23.380
as a cancer patient, they've been through so many CT scans. And nowadays we do PET scans. We follow up
00:22:28.300
with annual PET scans after the fact, which are not only the CT, but you've got a radioactive
00:22:32.080
isotope that's being injected into them. And we just really don't see. Now, there are certain
00:22:37.000
situations where you are giving a, for example, an intravenous therapeutic dose of radiation,
00:22:41.980
say for thyroid cancer or things like that. There's certain new theranostics that are out there.
00:22:47.220
In those situations, you have to be concerned because they can get into the multiple,
00:22:51.060
get into a sievert range. But when you're in these millisievert ranges, it's so important to do these
00:22:55.280
studies. The benefits of mammograms are so proven. Dental x-rays, I don't really think twice about them.
00:22:59.960
Okay. By the way, just on the PET scan, so if you do a PET CT, for example, which again,
00:23:05.460
these are not routinely done. These are typically done in oncology patients only. But just for my
00:23:10.380
own understanding, are we talking 50 to 100 millisieverts if you're doing a whole body PET
00:23:15.040
CT? I think it can be in that range. Yes. I think that's exactly right. So PET CTs are relatively new,
00:23:20.200
but up until maybe a decade ago, the PET scan was independent of the CT. They would do them separately,
00:23:25.340
but the data is so much better when you have the anatomical CT data overlay with the PET that
00:23:30.500
whatever that extra dosage is, I think it's well worth it in terms of the resolution of what we're
00:23:34.520
able to see and what we're able to gain from that information. Okay. So now let's pivot from the
00:23:41.200
diagnostic to the therapeutic. Is it safe to say that the majority or the most prevalent or common
00:23:50.900
type of radiation oncology treatment would be for breast cancer? Breast and prostate are the number
00:23:56.820
one and number two, depending on what patient population you're talking about. Prostate may even be a little
00:24:00.860
bit higher. And this goes back to the 80s when the trend from doing a Halsteadian type of radical
00:24:07.220
mastectomy was falling out of favor and the randomized data was obtained in the 80s showing that a lumpectomy,
00:24:13.240
breast conservation, which is lumpectomy followed by radiation, has the same outcomes in terms of
00:24:18.640
overall survival as a full mastectomy. That's when breast really took off in the 80s. And around
00:24:23.800
the same time is when prostate radiation started becoming a thing. But at the time, radical
00:24:28.720
prostatectomy was obviously still king. But now in the 2020s, I think prostate has taken off and it's
00:24:34.860
probably close to matching breast cancer now. Those are number one and number two, but we also do,
00:24:38.920
depending on where you are in the country and what your affiliation with the hospital is, tons of CNS,
00:24:43.820
lung, lymphoma, GI, not colon, but more rectal and anal distal GI cancers. Even in the pediatric
00:24:51.380
world, we try to avoid radiating children, but it's a very big part of that as well. So we use
00:24:56.320
it for almost all types of cancer now, actually, all solid tumors anyway. Well, let's talk a little
00:25:00.620
bit about breast cancer, given how common it is. I'll tell you something funny. Despite training at
00:25:06.260
Hopkins, I never once did a radical mastectomy. I mean, it was already long gone from clinical practice
00:25:12.600
25 years ago. And again, just for listeners to make sure they understand the difference between a radical
00:25:17.380
mastectomy and a mastectomy, or what's called now a modified radical mastectomy, the current version
00:25:24.200
of a mastectomy removes all the breast tissue along with the lymphatic tissue in the axilla. Certainly,
00:25:31.340
I did more than my fair share of those, but the radical mastectomy, the Halsteadian procedure,
00:25:36.360
removed also the entire musculature of the pec, pec major, pec minor, the whole thing. It basically
00:25:43.320
was a disfiguring operation that left the woman with nothing but ribs. Imagine what it's like to
00:25:51.680
not even have pec muscles. You sort of take for granted what you need to do to move your humerus.
00:25:57.880
And yeah, to think that it's only been 40 or 50 years that someone had the courage. I think it was
00:26:03.500
probably Fisher. Right. Fisher's big study in the 80s, which now we have 40-year data from that.
00:26:09.020
And it's interesting how now even the modified radicals are relatively rare. We still have some
00:26:13.580
advanced cases that they have to go that route. But we see tons and tons of patients now who are
00:26:18.420
so much happier, their quality of life is much better. By just having a simple lumpectomy,
00:26:22.720
a central node biopsy, and if it's all negative, especially if they've had their mammograms,
00:26:26.340
you get a small T1 or T2 tumor. We give radiation to the whole breast following that.
00:26:31.160
And the radiation is, again, fractionated into small daily bits. They'll get somewhere in the
00:26:35.880
neighborhood of, these days, it's actually only about three weeks of treatment, maybe about,
00:26:40.180
I say, 40 gray in roughly 15 fractions. We used to give, even when I was in a couple decades ago,
00:26:46.440
we were giving 50 to 60 gray. It was quite a bit higher dose. But the 40 gray in 15 fractions to the
00:26:51.940
full breast, and with the modern technology, we can cover the breast tissue without a significant
00:26:56.980
heart or lung dose. We can even use tangential beams, even if it's a left-sided tumor,
00:27:00.920
to stay away from the heart, which is things that we couldn't do very well in the past.
00:27:05.400
The overall and disease-free survivals are pretty much comparable to someone who had a modified
00:27:09.620
radical. Yeah. For folks who want to know more about that, Sid Mukherjee in, I think it was in
00:27:15.180
The Emperor of All Maladies. Yes. Has a chapter on this. Fantastic book and one of your best podcasts.
00:27:20.200
Love that guy. Yeah, he's a legend. So let's talk about that. So a woman has a stage one or a stage
00:27:25.820
two breast cancer. Typically these days, I think they're moving mostly to neoadjuvant chemo before
00:27:32.420
resection. Yes, in a more advanced case. But if it's a typical T1 or even a small T2 that we see,
00:27:38.520
they may not need any neoadjuvant therapy. They just will have their lump. If it's, like I say,
00:27:42.700
a one and a half centimeter mass that's easily resectable, they'll remove that just without any
00:27:47.240
neoadjuvant treatment. And we'll do adjuvant radiation and then potentially, depending on the
00:27:51.600
receptor status, adjuvant hormone therapy, which is the domain of the medical oncologist. But we
00:27:56.100
still work with them. So just surgery followed by three to four weeks of radiation. How long after
00:28:00.800
surgery can you begin radiation? Wound healing, we give them a little bit of time. We generally
00:28:04.880
do our CT-based simulation and three-dimensional planning maybe two to three weeks after their
00:28:10.120
surgery. And then by the time, it takes about a week to do all of our computer programming. And then
00:28:13.880
we'll start the treatment within three to four weeks post-op. So tell me a little bit about that.
00:28:17.880
I was completely unaware of that. So I'm a woman, I've had a lumpectomy. Sentinel node was negative.
00:28:24.140
So I've got an incision about this long for the listener, five centimeter, six centimeter incision.
00:28:29.680
They've probably closed it with beautiful internal sutures. I've got some steristrips. They're off in
00:28:33.780
a week and I've got a nice little scar a week later. I come and see you how many weeks after that?
00:28:38.360
I usually will see patients for consultation. A lot of times the breast surgeon will send them prior to
00:28:42.160
anything being done. So I'll see them for their initial consultation ahead of time. But then we plan on
00:28:46.280
doing what's called a planning procedure or a simulation where we're going to put the patient on the
00:28:50.460
table and essentially do a dry run for their treatment, usually a couple of weeks after treatment.
00:28:55.520
And that involves essentially positioning the patients. Typically for a breast patient, they'll be prone
00:28:59.420
with their arm behind their head. We call it the movie star pose to get the arm out of the way of the
00:29:03.440
axilla essentially. So by putting them in this position and then putting them on a wing board that'll
00:29:07.420
slightly elevate their torso. And there's a lot of different geometry here that we can use.
00:29:12.000
Back in the old days, they had all kinds of ways of doing plaster casts and things like that. But
00:29:16.380
we essentially do now, we'll use what we call a vac lock, essentially a bean bag with a vacuum
00:29:21.160
port. And the patient sinks into the bag, we suck all the air out of and lock it, becomes a rigid
00:29:25.380
cast of their body. And that way they fit into the groove that we've made for them. We'll actually
00:29:29.500
form it and mold it around their elbow so they're comfortable. Many times with patients who've had an
00:29:34.260
axillary dissection, they may have a little bit of scarring, a little decreased range of motion to be
00:29:38.220
able to get their elbow back there. So we'll work with them the best we can. Whatever position we get
00:29:41.860
them in, we do a CT in that position. And that's the position we have to reproduce for the daily
00:29:47.020
treatment. And the key there is that when they have their arm out of the way, we have to have room so
00:29:51.900
that the machine can move around from different angles. The actual radiation machine has a gantry
00:29:56.160
that can move really 360 degrees, can treat from any angle you want. But we have to be able to model
00:30:01.080
tangential beams. We don't want direct anterior field that's going to radiate the breast, but the
00:30:05.780
photons are going to go right into the chest. By using an angle, we can cut across the surface and
00:30:10.900
actually shape the beam to match the curvature of the chest wall. So we cover the entire thickness
00:30:15.720
of the breast tissue, or even in the case of an advanced, maybe a T4 patient, something like that.
00:30:21.160
We may even do this post-mastectomy, so you're treating the full chest wall. And we go a little
00:30:25.200
deeper below, into the ribs, into maybe the first inch of lung tissue below that. But by using these
00:30:30.120
tangential beams, that really minimizes the treatment, the photons damaging the lung tissue.
00:30:34.900
So all of that is planned ahead of time. We do a CT scan.
00:30:37.580
Just to be sure, planned pre-resection, because you're seeing the tumor itself?
00:30:45.720
Post-resection, you'll see a tumor bed. The lumpectomy cavity is obviously
00:30:48.600
clearly visible. It's a fluid pocket on CT. So I'll scan the whole chest. Takes about a week. I
00:30:53.920
have a whole team. I have a wonderful staff, a radiation dosimetrist that helps do the computer
00:30:57.960
planning, and then a radiation physicist that actually calibrates the machine prior to actually
00:31:02.620
starting the patient. So we do the scan. Of course, the CT scan is two-dimensional slices,
00:31:06.820
but we have three-dimensional modeling software. So I'll have a full 3D model of the patient I can
00:31:13.120
It varies. This is not a diagnostic scanner thing. So usually something like two millimeters,
00:31:17.760
three millimeters. We don't have to go super high resolution. And so that way, once it's
00:31:21.940
reconstructed, then I can have a nice idea of what angles to bring the beams in at, because every
00:31:27.040
person has a slightly different curvature to the chest wall. You're going to have to customize the
00:31:30.560
anatomy, different breast sizes. We have all kinds of different techniques, so I won't go
00:31:34.440
too much into the details. But if someone is very large-breasted, we could even treat them prone,
00:31:38.440
have a special pillow to allow the breast to hang down.
00:31:40.520
And it's also, I'm guessing, where the tumor was in the breast. So if you have large breast
00:31:44.380
and a superficial tumor, definitely prone would be amazing. The tumor bed is so far from the patient,
00:31:51.620
That's true. But technically, what we call the clinical target volume, the area that we're trying
00:31:56.300
to radiate would actually include the entirety of the breast tissue, even all the way down to the
00:32:00.920
chest wall. So there's two different ways. There's full breast radiation, which is what most people
00:32:04.640
get. But what you're describing actually is partial breast. We would just target the lumpectomy
00:32:08.660
cavity. And that can also be done. We save that for usually for older women who have a very small
00:32:14.600
tumor. And when I say older women, it's more because of the fact that the remainder of the
00:32:19.380
breast remains untreated. So a local recurrence is a little bit more likely in someone that has not
00:32:24.100
had full breast radiation. But in a selected subpopulation of small breast cancers, in some
00:32:29.320
with a very large breast, you can do partial breast where you're only targeting the lumpectomy
00:32:33.400
cavity. But for most of our patients, we actually do treat the whole breast as standard of care,
00:32:38.260
plus or minus the axilla. That's where the pathology comes in. Because if they did have a
00:32:42.340
positive lymph node, then we have to go after the axilla and sometimes the supraclavicular and even
00:32:49.360
Okay. Yeah. So this is infinitely more involved than I thought, which means I'm not the only
00:32:54.040
one that probably was ignorant of what is involved. How long does each session take?
00:33:00.400
When they're actually on treatment, it's about 15 minutes, sometimes even a little bit less than
00:33:04.020
that. Some of the newer machines can deliver the beam even faster. But when I say 15 minutes,
00:33:08.480
I'm talking about, I have four patients an hour typically. So in and out of the room in 15. So
00:33:12.860
that includes getting them on the table. The key thing for accuracy and reproducibility is
00:33:17.720
positioning. So the reason we made that mold and we've not only did we get them in position,
00:33:21.900
but I've also got a couple of dots on their skin to use as reference marks to make sure that the
00:33:26.440
patient is in the correct position. That whole process probably takes five minutes every day
00:33:30.800
when the patient gets in the room and then maybe another five to 10 minutes for the actual beam
00:33:35.040
to be on. And my favorite thing is to come in the room after the patient's first treatment. And then
00:33:40.060
the most common question I get is, hey doc, when do we start? And I'm like, no ma'am, that was,
00:33:45.700
they're like, really? That was it? Because the patient feels nothing. So the machine will go through
00:33:49.120
its various angles. It's pre-programmed. The entire process is about 15 minutes a day and
00:33:54.300
they can leave feeling the same as when they got there, just like getting any x-ray. They jump in
00:33:58.080
their car and go right back to work or to the gym or the golf course. When did this become so automated
00:34:02.660
with the robotic arm and stuff? Did you do this in your residency or were you the ones manually
00:34:07.080
doing that in residency? So I was in residency in the late nineties, early 2000. So it was a very
00:34:12.280
interesting time because we were at the cusp. My first year of residency and I was at UTMB in Galveston.
00:34:17.480
And it was a combined rotation with MD Anderson. So we were at a time, this is 1998 we're talking
00:34:22.120
about, where at the end of the old era, we didn't even use CT planning. We just had a couple of
00:34:26.560
orthogonal films and we were literally drawing our tumor volumes out with a grease pencil on a
00:34:31.140
physical x-ray and using that cutout to go trace a styrofoam negative and make a metal or a lead alloy
00:34:38.860
block, which you would slide this, basically this aperture in the path of the beam. That's the way it was
00:34:43.040
done for decades. And so we were still doing that when I started residency. But by the end of
00:34:47.920
residency, we had full-on CT planning, where now we're doing a full CT scan, doing everything
00:34:51.940
virtually. And of course, it's far more precise and you can model multiple different iterations.
00:34:57.480
Okay, do I want a beam coming in from this angle? Do I want to bring in an orthogonal beam from here?
00:35:01.880
Do I want to block out a little bit more of the chest wall to get the heart dose down? I can see all
00:35:07.400
that stuff now. So by the time I finished residency, we were basically doing what we do now,
00:35:11.220
albeit with much slower computers and just being in the infancy of that, it was probably more like
00:35:15.660
20 to 30 minutes per patient. But the last 15 years, roughly, to answer your question,
00:35:20.380
things have been much more automated. And instead of having lead blocks that you're sliding into the
00:35:25.040
path of the beam, now everything is shaped in the head of the beam by our computer. So you hit a button
00:35:29.280
and when I've already programmed the treatment planning values, the machine knows how to shape the beam to
00:35:35.260
match the aperture of whatever you're trying to do. So that's all fully automatic now. So the therapist
00:35:40.340
job, we have a radiation therapist who actually positions the patient in the room. They get them
00:35:44.640
in position, they take a picture x-ray first, either a cone beam CT, which is a low dose CT,
00:35:49.940
or just a PA in a lateral film. And we actually overlay that with our planning imaging to make
00:35:55.540
sure that the original reference from the planning day matches today's image. The machines will
00:35:59.760
actually superimpose the daily image with the reference image. So everything is automatic.
00:36:04.520
I can say, okay, are we directly on? If everything lines up correctly, then we literally have two
00:36:09.100
images that look identical. I just see one image, which if it's slightly off, if there's even a few
00:36:13.260
millimeters this way or that way, we account for that by moving the table. The table is motorized.
00:36:17.920
So the patient will be laying there and they'll feel it move just a few millimeters this way or that
00:36:21.300
way until we have perfect concordance between the daily setup and the original. That's really,
00:36:26.880
really improved our accuracy. And the regional miss, the geographic miss, which was a problem in the old
00:36:32.440
days when we didn't have digital imaging and all this stuff is essentially gone now.
00:36:36.840
The actual radiation beam is generated by what? The ion is generated by?
00:36:41.240
So that's another thing that has changed. Now, essentially, when I say now, the last basically
00:36:45.560
30 years, most machines in the US are linear accelerators. So these are artificially generated
00:36:50.840
x-rays. It's essentially accelerating electrons through a long vacuum tube, an essential electron gun.
00:36:56.940
And at the very end of the tube, you've got a tungsten target. And so the electrons hammer that
00:37:02.760
target and then they shower photons out. So you're generating the x-rays that way. And this has been
00:37:07.240
done actually, I think your alma mater, Stanford, had the very first one in the US, the medical linear
00:37:12.380
accelerator. But prior to that, they were using these for atom smashers and they have the gigantic
00:37:16.260
machines that were used for physics. But it started in London, I think in 53. And then I think in the
00:37:21.220
late 50s, Henry Kaplan at Stanford had the first one. So we're essentially still doing that even
00:37:26.020
today, what, 70 years later. But the key difference is how we're able to shape those photons once they
00:37:31.280
come out of the machine now. And so when the actual photons are coming out, they're completely
00:37:35.880
unfiltered. It comes out in a cone shape and it diverges just as any light source would. You know
00:37:40.340
how when you hold a flashlight to a wall, you get a nice precise circle. As you pull the flashlight
00:37:44.660
away, it diverges. So we have filters and we have what's called the multi-leaf collimator that can
00:37:49.420
actually shape the beam, as I mentioned earlier, that can actually match the anatomy of the patient.
00:37:53.920
But now that's all done automatically. We program it ahead of time as opposed to the old days when we
00:37:58.280
had to use lead blocks that were actually physically blocking the beam. But basically, the LINAC has
00:38:03.260
been the standard. Prior to that, we were using a cobalt-60 machine, which is essentially, it's not
00:38:07.700
even a machine. It's basically just exposing a patient to a radioactive isotope and then shutting
00:38:11.940
the jaws again. And actually, those are still in use in most of the world. There's a few left in the
00:38:16.060
U.S., but they've mostly been decommissioned now because the LINACs have taken over.
00:38:20.440
When you say that a typical treatment might be 15 gray over the course of the three weeks,
00:38:30.900
So roughly 2.5, 2.6 gray per day. And you're right, times 15 treatments. So you're getting roughly
00:38:36.500
40 gray to the breast. And then we usually actually do a boost. So we'll give what we call a tumor bed
00:38:42.260
boost. We give a little extra dose to just the lump itself, the lumpectomy cavity itself. And
00:38:47.220
there was a couple of French trials that showed that adding an extra 10 gray over an extra five
00:38:52.040
days, so two gray times five, just to the lumpectomy cavity itself improves local control over just
00:38:58.340
Okay. That's actually what I was going to ask. I was going to ask, if the 40 gray
00:39:01.200
is distributed completely uniformly across the breast, the answer is no. It is, but then you have that
00:39:07.740
an extra boost. It's a customization based on the patient's pathology. I'll occasionally have a
00:39:12.480
patient that the breast surgeon will call me and say, hey, Sanjay, we did our best, but we had a
00:39:16.940
persistent positive margin. I went back and did a re-resection and there's still a positive margin,
00:39:21.380
or maybe the positive margin is at the chest wall. They can only go so far. In that case,
00:39:25.300
instead of giving a 10 gray boost, I might give a 16 gray boost or something to account for,
00:39:29.640
instead of just treating microscopic disease, potentially macroscopic residual in that sort of
00:39:34.120
situation. So every patient's a little different. And then the axillary nodes themselves are
00:39:38.640
normally not treated in an early stage patient, but depending on the risk factors, if it's a very
00:39:43.020
large tumor or if there was a positive central node, maybe an incomplete axillary dissection,
00:39:48.060
in many cases, we end up treating the full axilla. And in some cases, when it's advanced disease,
00:39:52.680
we end up treating level two and level three. So you end up getting the super clav as well.
00:39:56.980
If we go back in time to 25 years ago, 30 years ago versus today,
00:40:00.900
what are the typical side effects that a woman experiences from this treatment? And by the way,
00:40:06.280
was she typically getting 40 gray 25 years ago, or was that a little more? I think you said,
00:40:11.380
and now they've come down a bit, it was sort of 50, 60 gray.
00:40:14.080
This brings up a point I need to kind of emphasize. It's not so much the total dose,
00:40:17.580
it's the dose per fraction. So how quickly are you getting it? So the standard of care was actually
00:40:22.120
50 gray rather than today's 40-ish gray, but it would usually be given in two gray per fraction
00:40:27.840
daily doses rather than the 2.6, 2.7 that we're using now. So the effective dose,
00:40:32.820
when you take into account, there's a whole radiobiology lecture that we're not going to
00:40:36.220
bore people with, but taking into account the dose per fraction and the total dose,
00:40:40.800
the biologically equivalent dose with the BED is roughly the same now at 39.9 gray given in 15
00:40:47.740
treatments versus the old 50.4 gray that was given in say 25 to 28 treatments. So it was a longer
00:40:53.880
process, you're right. And we still do that in some cases. And this comes back to another question
00:40:58.560
you asked about, about the homogeneity of the dose. And so our goal, of course, is to have 100%
00:41:04.200
coverage of the whole breast. But the reality is the way that photons are going to be interacting
00:41:08.900
from different beam angles and whatnot, you're always left with hot spots and cold spots.
00:41:13.780
And so the biggest difference between what we're doing now versus the old days wasn't so much the
00:41:17.780
total dose, it was the actual homogeneity that you touched on. So the heterogeneous old way of doing
00:41:23.120
things with a cobalt machine or with a low energy x-ray, unfortunately meant that there were hot
00:41:27.560
spots and cold spots in the breast. And that of course could either be manifested as scar tissue
00:41:32.060
if it's a hot spot or heaven forbid, a geographic recurrence if there was a area that was underdosed.
00:41:38.040
So with the modern computer planning, we were much more homogeneous. So even though you may say,
00:41:43.440
I got 50 gray back in 1995 and now I'm getting 40 gray, you're now getting 40 gray in two and a half
00:41:49.660
gray fractions, which is equivalent to the old 50. Plus we don't have 150% hot spot and a 60% cold
00:41:56.660
spot. We have a nice 100% match all the way across. It's like a CAD CAM type of thing. I'm about as close
00:42:02.520
to an engineer as an MD can be. And so we do actually simulate the dose distribution of the
00:42:07.980
radiation in the tissue. In the modern days, we get a nice homogeneous dose. And therefore that goes to
00:42:14.040
your next question, which was what is the patient experience? Maybe not so much 20 years ago,
00:42:18.280
but more like 30, 40 years ago with the older cobalt machines, they would get a terrible dermatitis.
00:42:23.100
Many times it was moist desquamation confluently over the whole chest wall. Axillary desquamation
00:42:29.160
is always bad because of the friction of the arm. But with the modern treatment now with, first of
00:42:33.800
not using cobalt, using linear accelerators, the energy of the photons is higher, which means the skin
00:42:40.100
dose is slightly lower. So you're getting maybe a hundred percent on the skin rather than 150% like you
00:42:46.100
once did. So we don't see anywhere near the skin reaction that we used to. It's more of a, maybe a
00:42:51.880
grade one or a grade two erythema. So mild redness, or maybe sometimes a little bit of sunburn, but nothing
00:42:57.480
as severe as we used to. So these days, patients do still get a sunburn. We give them a little free samples
00:43:03.000
of Aquaphor. They can use an aloe vera plant if they have it, just your normal type of skincare stuff,
00:43:08.260
as opposed to the old days when we were actually treating essentially burn victims with
00:43:11.760
silver sulfadiazine and heavy duty narcotics and things like that. The modern era, it's so much
00:43:17.300
better than a lot of the patients, especially if it's someone that doesn't have a very large breast.
00:43:21.560
There's less energy being put into a smaller size person. They don't get anywhere near the skin
00:43:26.000
reaction. And that's why if you did have a very large patient, we actually still use the old 50 gray
00:43:31.320
in 25 because you're giving less dose per day. And you do have a very large breast where you're going
00:43:36.860
to have areas that are going to have hot and cold spots. Sometimes that's still needed. So we have
00:43:41.700
to tailor it to the individual is, I guess, my bottom line there.
00:43:44.980
Did anybody ever look at when you had the very disparate hot and cold spots and follow women
00:43:51.980
Was there any association between the cold spots and recurrences?
00:43:54.460
There certainly is. And so the problem was, is that in the old days, you didn't have computer
00:43:58.240
modeling. And actually the old school physicists got to give your hats off to those guys that had
00:44:01.740
slide rules and probably abacuses or whatever the heck they had back then. You couldn't really tell
00:44:06.080
exactly where the hot and cold spots were by actually having a computer show you. You had to go based
00:44:11.100
on the fact you choose a photon energy and you know what the dose distribution at various depths
00:44:16.320
is. And so you would try to minimize that by again, having beams coming in from different angles.
00:44:21.060
And then by using multiple angles and multiple fields, you could paint in the dose as best as
00:44:26.240
you could. But yes, certainly there were issues where as you get deeper into the tissue, the dose
00:44:31.560
would be lower. And then this is again, before my time, but there certainly were studies showing
00:44:36.440
that there were geographic misses. That was obviously not good, which sometimes would lead
00:44:40.220
to like a salvage mastectomy or something like that. But in the modern era, not so much.
00:44:45.520
What is the impact of breast implants in this type of treatment, either saline implants or
00:44:50.960
the older, well, actually they're not older now, they're back in vogue, right?
00:44:55.540
Either way, the x-rays we use, they are not at all affected by that because it's essentially
00:45:00.480
Pardon my ignorance. I completely forget. Are those implants typically under the peck or between
00:45:08.640
I think most of them we see are actually under the muscle.
00:45:11.980
Mm-hmm. But I've seen them both. Even now, the plastic surgeons have different criteria
00:45:16.040
for that. But regardless of what it is, if it's under the peck, then of course, it's really
00:45:21.120
It's not a huge issue, but the radiation will still affect that area. But typically these
00:45:25.320
implants are pretty tolerant of that. The only issue down the road is they may have
00:45:28.800
a capsular contracture or something from fibrosis. The bigger challenge we run into
00:45:33.220
is for our post-mastectomy patients who are going to be reconstructed and they have expanders
00:45:37.920
put in. And that's where the relationship between the radiation oncologist, the surgeon,
00:45:44.240
Explain to folks what expanders are, how that works surgically.
00:45:47.680
So essentially what's happening is when you have a full mastectomy, if a patient wants
00:45:51.140
to have their breast reconstructed later on, the breast surgeon will remove the breast,
00:45:55.300
but then the plastic surgeon will come in and place some sort of a placeholder to allow
00:46:00.080
the soft tissue and all the connective tissue and the skin to stretch to allow for future
00:46:04.600
implant placement. And so those tissue expanders, they can actually inject saline into them with
00:46:10.220
a port and gradually stretch them with time. That's normally what they would do if there
00:46:14.800
was no radiation involved. Again, most mastectomy patients really don't need radiation because
00:46:19.440
this gets away from what we mentioned earlier, where breast conservation is lumpectomy only.
00:46:24.120
But there are some patients with a full mastectomy who are going to get reconstructed.
00:46:27.820
So they come to me when I do their CT scan, they have this expander in place from the breast
00:46:32.300
surgeon. So we have to, again, modulate the beams and we treat the entire chest while we
00:46:37.300
make sure we're covering everything. But simultaneously, we have to make sure that we
00:46:40.960
don't have those hot spots in the area of the expander where potentially you could cause
00:46:45.540
scarring and fibrosis and cause the expander to have to be removed, have the plastic surgeon
00:46:49.980
have to revise it. That becomes a whole nother hill of beans there that we don't like to mess
00:46:53.860
with. But we have techniques now to be able to keep the dose off of them. And again, as
00:46:58.380
you mentioned earlier, whether it's silicone or saline, it's roughly the same density. But
00:47:02.520
some of these tissue expanders have bits of metal in them. They may have other artifacts.
00:47:06.460
And so when I'm treating with photons, with x-rays, depending on what you're hitting, the
00:47:11.700
effect is based on the density, the atomic number of that tissue. So metal behaves very differently.
00:47:16.840
Bone behaves differently from air. But when you're in the spectrum of saline, tissue, water,
00:47:21.540
it's all basically the same. We can model all that very much like, I'm getting ahead of myself,
00:47:26.260
but very much like when we have a prostate patient with a prosthetic hip, a piece of metal right next
00:47:30.620
door, we're able to compensate for that with the modern computer treatment planning systems.
00:47:35.720
Do women experience any systemic symptoms from radiation like nausea or vomiting, or is that
00:47:41.580
pretty much? Not at all. The only time we see radiation patients who have nausea or vomiting,
00:47:45.880
it's a lot of times for other sites, they may get concurrent chemo radiation where the chemo
00:47:49.820
could be responsible. But for breasts, we don't do concurrence, usually sequential. The only time I
00:47:54.440
really see radiation-induced nausea is if I'm treating an esophagus or a pancreas or something
00:47:58.440
that's treating in the abdomen or somewhere along the GI tract where nausea is more of an issue,
00:48:02.920
typically not for breasts. Okay. Let's talk about prostate, which is obviously also the bread and
00:48:08.520
butter of the field. So first off, which patients are typically being radiated?
00:48:13.520
The answer to that has been evolving. There was a time as recently as probably 20 years ago where
00:48:18.560
we only treated patients who were probably medically inoperable that the urologist would
00:48:23.200
say, hey, you know, this is a high-risk anesthesia patient. Let's send them to Dr. Mehta for radiation.
00:48:28.080
And that's a big reason why a lot of the older data was not as good for radiation because of the
00:48:32.940
patient selection criteria. But in the modern era, as we've gotten more and more precise and our
00:48:37.880
side effects have gone down and our cure rates have gone up, now it's pretty much wide open where
00:48:42.180
pretty much anybody who's eligible for surgery would also be eligible for radiation. So there's not that
00:48:46.640
big of a divergence as there once was. You've gotten to know Ted Schaefer, who's not only good
00:48:52.900
on the podcast, but is equally, let's just say, interested in cars. He sure is. So you, me, and
00:48:58.300
Ted have a lovely little text thread about cars. He and I may have another text thread in case our
00:49:03.940
teams meet in the playoffs as well. He's a big Ravens fan. So, and I'm from Houston. So I'm hoping we
00:49:08.660
get there. Let's talk about a patient that comes in to see Ted for a biopsy. They've got a Gleason
00:49:14.940
three plus four, and then another patient who's a Gleason four plus four or four plus five or
00:49:20.580
something like that. How does that patient navigate their way through the system as to whether or not
00:49:26.340
they need radiation or should they undergo surgery? And does androgen deprivation therapy necessarily
00:49:31.940
come with radiation? Or is there a scenario where you undergo radiation, but you don't require
00:49:37.780
androgen deprivation? So to answer your last question first, androgen deprivation for high
00:49:42.300
risk disease is certainly standard of care. Gleason eight or higher for sure. The Gleason
00:49:47.940
sevens are always a gray zone. And so a four plus three with high volume disease typically also do get
00:49:53.720
concurrent and adjuvant androgen suppression along with radiation. But one of the things that's really
00:49:59.160
changing now is I know Ted talked a lot about with the decipher score where they can look at the
00:50:03.380
chromosomes of the actual cancer cells and have a much more granular view of exactly are they truly
00:50:09.800
high risk? Or can you say that this one three plus four is more like a three plus three? So for a lot
00:50:14.540
of the three plus fours now with the decipher test, and there's also an AI test. I know you had a really
00:50:18.680
interesting discussion with your AI expert, and that wasn't too long ago, called Artera. And we're using
00:50:24.200
that. That's actually in the NCCN guidelines now. So that Artera test can help us differentiate between a
00:50:29.220
unfavorable and a favorable intermediate risk patient. I treated my own father not too long
00:50:34.540
ago. He was the first person I did this on. The Artera test is essentially they just use the actual
00:50:39.640
images of the H&E slides that were already done for the pathologist. And it's interpreted by a
00:50:44.640
machine learning computer that has been trained on hundreds of thousands of prostate images from the
00:50:50.060
old RTOG studies, the 94s, all the stuff that was done back in the 90s. And it can now come back and
00:50:55.280
say, okay, very much like decipher. It can say that this is a three plus four, but it's a favorable or
00:50:59.580
an unfavorable person in that subgroup. And so because of that, we can stratify better and actually
00:51:04.920
tailor it to where maybe a three plus four doesn't need androgen ablation at all. And maybe even some
00:51:09.760
four plus threes, if they come back low enough on the scale, you always have to talk about the side
00:51:13.960
effects and whatnot. But the standard of care was always to give concurrent androgen ablation for
00:51:18.360
intermediate risk. But now we're able to really take some of those people out of the equation with these
00:51:22.300
new studies. And is the main selling point, because most patients just want things taken out. I have
00:51:29.380
cancer, take it out. Is the reason that a person might select radiation therapy, especially if it
00:51:36.060
comes with androgen deprivation therapy, because of the sexual function and urinary function? Like
00:51:41.900
what's the main advantage? Those are number one and number two. Yeah. Lack of incontinence and lack
00:51:46.720
of impotence. But of course, when you have androgen ablation, that clouds things a little bit.
00:51:50.560
But typically, the number one thing we see is patients who don't want to deal with diapers.
00:51:55.840
And for the most part, although incontinence is still described to some degree in the literature,
00:52:00.860
in my personal experience, I don't think I've seen a single patient who came in
00:52:03.860
continent who left with anything less than that. There's no pads, there's no nothing.
00:52:09.220
And then of course, as I talked about with breast cancer, we can also focus very precisely on the
00:52:13.520
prostate itself. So the dose to the penile bulb, the dose to the rectum, the dose to the bladder
00:52:18.540
are so low now that the side effect profile is essentially zero from a radiation standpoint.
00:52:24.820
Now, they may be having hot flashes from the androgen deprivation and decreased libido and
00:52:28.940
fatigue, as you know. But on the radiation side, because we have all these tricks now,
00:52:33.020
very much like with breast, the way we can avoid the heart and the lungs, in the case of the prostate,
00:52:37.120
we can almost completely avoid the bladder and the rectum and even the penile bulb now.
00:52:41.320
So the quality of life, those are the reasons why people tend to choose radiation.
00:52:46.340
And I know we've talked about this before, you're just not seeing the proctititis.
00:52:50.320
Yes, almost none. In fact, I think Ted had mentioned in his last talk, there's a gel spacer that is
00:52:55.640
often inserted. It's an injection that's done transperineally, and it separates the rectum from
00:53:00.540
the bladder. But in my years of doing this, when you're very diligent about how you do this,
00:53:05.000
very much like a surgeon pays attention to the details, so do we.
00:53:07.840
I can actually trim the dose off of the posterior prostate and just make sure the dose fall off
00:53:13.240
between the posterior prostate and the anterior rectal wall is so rapid that the anterior rectal
00:53:18.800
wall is always going to get some dose, but usually it's not clinically significant.
00:53:22.920
And what we do to manifest, to make sure that that is a daily thing, because we're talking about
00:53:26.700
treating patients for multiple weeks, we actually coach the patient to come in with a full bladder
00:53:30.840
and an empty bowel. And by being diligent about that and imaging daily to double-check that,
00:53:35.860
in fact, the bowel is empty and the bladder is full, that allows those two organs to separate
00:53:39.840
from the prostate. And even a few millimeters of separation is all we need to take advantage of
00:53:47.840
And does the patient need to be coached to time their breath or anything as the beam is at that
00:53:56.940
Not so much for pelvic patients, but we do that for breast cancer, especially left-sided
00:54:01.820
breasts. So just to go back to that, you actually have a deep breath hold, which will get the chest
00:54:06.180
wall away from the heart. So we do that in the case of thoracic tumors, but in the pelvis,
00:54:10.240
the diaphragmatic position doesn't really make any difference. It's more about bladder and rectal
00:54:14.200
filling and emptying, respectively. That's much more important.
00:54:17.440
Everybody I've talked to who's had LASIK eye surgery always says they're so worried that they're
00:54:21.560
going to do something, they're going to flinch. And do patients feel the same way when they're
00:54:25.440
undergoing radiation? Like, what if I just flinch my pelvis or do something like that? It's going
00:54:30.760
I get that question all the time. And from a LASIK standpoint, I think I would be worried
00:54:33.740
about it. That's probably why I'm still wearing these Coke bottles, unfortunately. But in the
00:54:37.680
case of prostate cancer, first of all, the dose is given over the course of several minutes.
00:54:42.040
And then each of those fractions is, again, talking about one fraction out of multiple weeks. So
00:54:46.000
even if someone absolutely had a coughing fit or something like that, first of all,
00:54:50.280
we're watching them. We can stop the beam. We can stop it at any given moment.
00:54:53.720
But slight variations day to day, the biggest variations are going to be based on bladder
00:54:58.020
and rectal filling. We take that into account when we're doing the treatment planning. So
00:55:01.820
there should really be no adverse outcome. Because what I actually do is I'll map out
00:55:05.720
where the volume of the prostate is, and we will actually purposely expand that volume and
00:55:10.500
treat the full dose of radiation, even a few millimeters outside of the prostate to make
00:55:15.340
sure that there is any internal organ motion or anything like that, that we take that into
00:55:19.020
account. But typically, if someone's coughing or something like that, we'll just hit the
00:55:22.200
pause button and get them reset. And ultimately, it's not an issue.
00:55:25.760
What about patients that are inoperable? First of all, what leads to a patient being inoperable?
00:55:32.580
Typically, the urologists have already screened the patient. Everyone's first exposure is going
00:55:36.700
to be to what the urologist tells them. And luckily, in this day and age, I'm lucky we have
00:55:40.780
people much like Ted who are very open and who are very open to not just doing surgery, but who
00:55:45.600
actually look at the other options and present everything to the patient. But typically, a patient who maybe
00:55:50.140
was medically inoperable will certainly come to me. But even somebody who maybe is on the borderline
00:55:54.360
who wants to see both sides of the token, a general urologist will send them to a surgical
00:55:58.280
specialist and to me, and we'll go through all the pros and cons of everything. And really, what it
00:56:02.980
comes down to, to not belabor the point, it comes down to two things. You want to be cured.
00:56:07.280
Cure rate is key. But quality of life is equally important, if not more important, for most people.
00:56:12.400
And so now that cure rates with our modern focused radiation allow us to get such a high dose
00:56:16.880
into the prostate, we can say that they're essentially equivalent to surgery. So we don't
00:56:21.080
have that deficit like we did 20 years ago when our fields weren't as precise. It was sort of the
00:56:25.380
shotgun approach versus our sniper approach. Now, because the cure rates are better, then it really
00:56:30.320
comes down to the quality of life changes. And that's where there's a spectrum of things.
00:56:34.840
Now, is this an apples to apples comparison? Because the patient who undergoes the robotic
00:56:41.880
prostatectomy today does not go on androgen deprivation therapy. They get to walk around.
00:56:47.660
In fact, you've probably heard Ted on the podcast, he says, we'll give those patients TRT if they're
00:56:51.920
hypogonadal. Why does the patient after radiation therapy still need to be androgen deprived if,
00:56:59.640
in theory, the radiation is as effective as the surgery?
00:57:03.780
That comes to a key point where it's trading one thing for another. You don't have the incontinence.
00:57:07.980
You don't have the, at least the short-term risk of impotence like there is from surgery. You don't
00:57:12.260
have the penile shortening or whatever other sort of things that they have to deal with. But you have
00:57:16.540
to deal with hot flashes and decreased libido and whatnot. But again, most of the patients who are
00:57:22.280
intermediate or high intermediate risk are going to, if they end up not having a negative margin or
00:57:27.320
seminal vesicle invasion after prostatectomy, they're still going to come to me for radiation
00:57:31.280
anyway. And they're still going to need to be on androgen ablation. So there's a significant
00:57:35.840
number. Now, these days we'd certainly treat a lot less Gleason 6 than we used to. We observe
00:57:40.260
most of them. But there's a lot of Gleason 6 folks that even in this day and age will choose to have
00:57:45.160
radiation just because it's maybe a little bit more aggressive form of watchful waiting. And in that
00:57:49.580
case, there is no androgen ablation and they just glide through the whole process.
00:57:53.180
Has there been a trial of Gleason 3 plus 3 watchful waiting versus XRT no ablation?
00:58:00.340
No, unfortunately there's no actual trial. There's just observational studies.
00:58:05.260
Oh gosh. And obviously you can't figure out what the biases are, but what do those observational
00:58:10.880
People don't die from Gleason 6 disease, as we all know, because quality of life they do so
00:58:14.880
well with the radiation, there is just less of a chance of it progressing to a 7. And when they
00:58:19.620
come to me, it's interesting the different patient populations. I also get people, this is not
00:58:23.420
mainstream, but I get a lot of transplant candidates who need a renal transplant and they cannot get
00:58:28.040
their transplant unless they're cancer-free. Even if it's one core of a Gleason 6, they're
00:58:32.420
ineligible for their transplant. So those guys I will certainly treat, but I've been following them
00:58:36.920
now for 20 plus years that we've been doing it. Quality of life, they do so well. And this way,
00:58:41.400
they don't have to worry about androgen ablation when they do become a Gleason 7.
00:58:44.620
So it's really interesting. There would be a very interesting and elegant study taking,
00:58:51.040
let's call it medium to high risk 3 plus 3s. So people based on family history or some other
00:58:57.500
phenomenon, genetic or otherwise, you randomize them to watchful waiting versus radiate them
00:59:05.860
without androgen deprivation. I mean, you'd have to do this as a very long-term study. So the question
00:59:11.180
is, outcome number one could be conversion to 3 plus 7 requiring surgery and or androgen deprivation
00:59:19.020
therapy. And then of course, outcome two, the very long-term outcome would be overall survival.
00:59:23.160
That's the key. That's why these haven't been done. You wouldn't need decades to do a trial.
00:59:27.660
But it certainly would be interesting to see what it would show. But the real world
00:59:30.820
observational studies show that all the Gleason 6 guys, I would say until maybe a decade ago,
00:59:35.760
we did a lot of Gleason 6 patients. They mostly were sent for radiation.
00:59:41.260
I guess it's a combination of different things. People have different levels of tolerance for
00:59:44.800
watchful waiting. In the pre-MRI days, everyone had to have an annual biopsy. And that alone is more
00:59:50.980
anxiety invoking than really the radiation is. Not to mention, we'd see a fair number of folks with
00:59:55.560
urosepsis and complications from that. So now in the MRI era, we don't really see that anymore,
01:00:00.760
but that was done very routinely. And because the patients had so little proctitis and cystitis,
01:00:06.160
especially in a Gleason 6 where not only am I not worried about pelvic lymph nodes, I'm not even
01:00:10.900
really worried about the seminal vesicles. So my field is very small, which really minimizes the
01:00:16.240
side effects because the bladder, a full bladder, when it's actually full, it'll move superiorly and
01:00:20.900
anteriorly where the dose is close to zero. So most of these patients, they just kind of laugh
01:00:25.200
and say, I'm coming in for my daily treatment and I'm right back to my normal life again.
01:00:29.340
In the absence of androgen deprivation, radiation has become very simple for prostate patients now.
01:00:34.480
And again, what fraction of Gleason 7s can do radiation without requiring androgen deprivation
01:00:43.380
That answer would have been zero probably five years ago, even as recently. But now with Artera and
01:00:48.320
Decipher, it's probably, I'd say a quarter of them don't need it. If it's a 3-4 with a low
01:00:53.420
Decipher, low Artera score. And again, this is still an evolving area where I don't think anyone
01:00:58.540
has the exact answer, but that's what most people are doing nowadays. And even some 4 plus 3s that
01:01:03.680
have low Deciphers are potentially candidates to avoid that. And the biggest change in this has now
01:01:08.960
been our ability to do PSMA PET scans to follow up. Because otherwise, I think that the extra
01:01:14.300
androgen deprivation was more of a Band-Aid for not being able to see what's going on afterwards.
01:01:19.120
Now, if someone has a recurrence and you do a PSMA PET, I've got a guy that had treatment 20 years
01:01:23.980
ago with radiation. Now he's rising PSA. Otherwise, he'd just be stuck with ADT for years. Now I see a
01:01:29.840
positive periaortic lymph node on a PSMA PET. I can just treat that area and very successfully.
01:01:35.560
There's no long-term data yet, but it seems to be working really well. Similarly to how we would
01:01:39.660
use a FDG PET to target a lung tumor in the past. What about these patients that show up
01:01:45.020
with two spine mets? How effective is radiation there, given that that's a favorite spot for
01:01:50.560
a prostate too? You're talking about initial presentation with oligometastatic disease?
01:01:54.920
No, let's say, okay, we could talk about that or we could talk about post-treatment three years later.
01:01:59.360
So post-treatment three years later, palliative radiation does work very, very well. It would be
01:02:03.400
probably five treatments. You can even do what they call SBRT, which is stereotactic body radiation,
01:02:08.480
maybe in a single fraction. And it definitely is very good. We kind of joke about it and just
01:02:13.020
kind of spot weld that spot where it's not going to prevent something else from popping up elsewhere,
01:02:16.940
but that's extremely well tolerated. And usually it'll stop the progression at that site.
01:02:21.300
So there are people who had high risk disease. And to get back to what I mentioned earlier,
01:02:24.920
if they had a couple of spots like that at the time of initial diagnosis, now it's been shown that
01:02:29.600
you can treat the oligometastatic disease if it's in the bone only at the same time as the primary
01:02:34.360
lesion. And the outcomes are actually not significantly worse if it's just limited disease.
01:02:39.420
And what is a more favorable presentation, oligometastatic to bone or oligometastatic to
01:02:46.900
Bone, for sure. Actually, I had a guy walk into my office with a PSA of 1900. He looked just as good
01:02:52.920
as you or me. I actually took him on a TV show I did many years ago. It was kind of an interesting
01:02:57.300
story. 1938, 65-year-old guy, Mr. Macho, had never been to a doctor in his life, widower who decided
01:03:04.580
that he was dating a younger woman now. And she's like, if you want to be with me, you got to go get
01:03:08.000
checked out. Colonoscopy clear, blood work all clear. Oh, by the way, your PSA is 1900.
01:03:12.900
Which means the lab made a mistake. I mean, that's what you would think.
01:03:15.540
Yes, that's what you would think, except for his bone scan looked like a Christmas tree. And this was
01:03:18.580
in the pre-pet era. I mean, he had disease in every bone in his body with zero symptoms. So this is an
01:03:24.340
outlier situation. But in that situation, you need lifelong androgen deprivation and chemotherapy.
01:03:30.060
Back then, it was mostly taxol-based therapy. We didn't have all the second-generation
01:03:33.280
androgen ablation drugs that we do now, like enzalutamide. But at that time, when we saw that,
01:03:38.880
you know, he went and got chemo and got androgen ablation. When he came back to see me,
01:03:41.980
fully functional guy, perfect shape. His PSA was down to 1.5 with just the systemic therapy.
01:03:48.080
And at that time, the tumor board, we presented him, the decision was made to go ahead and treat his
01:03:52.600
prostate as though he was a de novo presentation because all the bone disease had resolved. He did
01:03:58.600
great. So you treated his prostate. And how long did he live? He's still alive. This has been,
01:04:04.940
I got an email from just about a year ago. So I think he, at least as of a year ago, he was 12 years
01:04:08.660
out, still doing great with zero side effects. He's on androgen ablation for life. So he's certainly
01:04:14.140
going to have issues from that. But overall, still very functional. How is this possible?
01:04:18.060
Well, what's the biology of that tumor that allows him to still be alive?
01:04:22.540
I don't think it's even necessarily just prostate. I've even seen it in breast cancer patients in the
01:04:27.140
small subset where it's bone only disease with no visceral metastases. Some folks can live for a
01:04:32.500
very long time with bone only disease. And I'm not sure what the answer to that is.
01:04:36.980
And has he suffered any debilitating fractures?
01:04:40.980
You would expect that at this point, but no, not even one.
01:04:45.540
Now he's in his, yeah, late 70s and has not fractured a thing and is still active. The guy
01:04:52.340
I'm not sure about that. But other than that, other than the hormonal aspects of it, yeah,
01:04:58.000
it's amazing. I've seen many, many people with four-digit PSAs that we get them down,
01:05:01.980
at least NED for some window of time, even if it's not that long.
01:05:08.380
Yeah. I think the highest I've seen is 7,500. That was a person that ended up passing away. But
01:05:12.780
the guy who was 1900, I think a lot of it is a function of, just like any other type of tumor,
01:05:17.260
he had all the other risk factors that were lined up. He was young, healthy, no other comorbidities,
01:05:23.660
Ted has told me about some of the most terrifying cases are the exact opposite. These guys that show
01:05:36.520
Right, right, right. And that's the thing. You get some of these really poorly differentiated
01:05:40.100
cancers that no longer resemble their prostate progenitor cells. They're very hard to monitor,
01:05:44.580
and a lot of them even don't even show up on a PSMA PET scan.
01:05:48.580
Anything else you want to talk about on the oncology side of this, as far as what should
01:05:54.160
people know as they're engaging with a radiation oncologist? What questions should they be asking?
01:06:01.260
It sounds like it's no different than surgery, where there's clearly a difference between good
01:06:08.220
surgeons and not so great surgeons. There presumably are people that take the kind of care you take
01:06:13.580
and agonize over the details. How can somebody find out if their radiation oncologist is practicing
01:06:23.040
It's difficult in terms of actual metrics. Even for the surgeons, like, you know, Ted is excellent
01:06:29.080
outcomes, but it's not like it's a published series.
01:06:31.720
And not only that, the best surgeons often are treating the hardest cases.
01:06:37.720
100%. It really comes down to finding someone who's got the experience. And in my case, because
01:06:42.100
we do so much prostate, I think I've done something close to, in the modern era, 7,000 cases,
01:06:47.880
probably 10,000 when you include the pre-image guided radiation days.
01:06:51.700
Someone who specializes in the area that the cancer is located in. So someone like me, I may
01:06:56.740
be extremely experienced in breast and prostate, but maybe for a pediatric malignancy, you're not
01:07:01.260
going to come to me. You're going to go somewhere or a CNS or something that's unusual. You have to
01:07:05.020
find the right tool for the job, but you have to just interview your doctor. I don't think there's
01:07:12.980
I think being very open with them and saying, yeah, exactly. And so ideally, maybe you come to
01:07:17.820
someone who knows something. Like I get a lot of patients who aren't familiar with the field,
01:07:20.840
but they'll have a patient, they'll have a family member that's a nurse or a dentist or a veterinarian
01:07:25.180
or whatever it is. Someone that has some medical background, they can say, okay, let me ask them
01:07:28.760
more specific questions. And these days with the internet, you can do all kinds of research in
01:07:32.800
terms of when I'm talking about matching my volume of the dose distribution to exactly conform to the
01:07:39.640
tumor volume. That's something that's very easy to talk about. But I mean, for an educated patient,
01:07:44.660
they can ask to see the actual computer simulations. A lot of my engineering patients-
01:07:48.520
I was about to say, engineers probably have an easier time than-
01:07:50.940
They do. And my engineering patients are really the only ones who do this. I usually pull out all
01:07:54.760
the graphs. I show them dose volume histograms with area under the curve for each organ. And you
01:07:59.740
can see, okay, the prostate dose area under the curve is huge. The dose of the bladder and the
01:08:03.460
rectum is super low. You can actually quantify that. But for a lay patient, it's hard. It's not
01:08:07.880
that easy to do that. I think a lot of it, you have to go with your gut too, in terms of this guy's had a
01:08:11.500
lot of experience. And the initial consultation is where it all comes down. I'll spend an hour with
01:08:15.500
a patient and go through every little nuance of what could and couldn't happen. And my main MO is
01:08:20.900
to sort of over-prepare them and have them be pleasantly surprised maybe when the side effects
01:08:25.260
aren't as bad rather than the other way around. It's hard to find the right person, but there's
01:08:28.900
a lot of good doctors out there. Let's spend a minute just on the brain, because I guess that's
01:08:33.900
sort of a unique case. I know it's not where you are-
01:08:38.480
Not as much as prostate and breast, but yeah, both primary and metastatic.
01:08:41.940
Yeah. So again, because the brain is such a sink for mets, A, it's a source of a lot
01:08:47.960
of primaries, but it's also where a lot of cancer spreads. It's often a place where you
01:08:52.600
can't operate, either because the tumor, the met or the primary is too close to say the
01:08:58.500
brainstem or something too vital. So radiation is a pretty common tool there. So talk about
01:09:03.900
the history of radiation in the brain and the spectrum of everything from whole brain radiation
01:09:08.700
to gamma knife and stereotactic and all sorts of things in between.
01:09:12.560
Sure thing. The main differentiating factor for brain patients is whether it's primary
01:09:16.260
or metastatic disease. And although primary brain tumors are relatively common, they are
01:09:20.860
dwarfed by metastatic disease. So the vast majority of what most radiation oncologists see when
01:09:25.760
you're treating CNS is going to be usually lung, especially small cell-based brain metastatic
01:09:31.440
disease. And so in those situations, the trend used to be where everyone would get whole
01:09:35.840
brain radiation. But now with the advent of stereotactic radiosurgery, which is more focused,
01:09:41.080
precise radiation, the newer data shows that you can actually just treat the area of metastatic
01:09:45.520
disease as a delineated on an MRI scan and not necessarily radiate the whole brain like
01:09:50.580
we used to. But for decades, everyone got whole brain radiation. And for the most part,
01:09:54.400
they did all right. But the problem was you're looking at a patient population that maybe doesn't
01:09:57.780
have that much of a life expectancy. Now that systemic therapy, immunotherapy, everything has
01:10:02.360
gotten better, especially in the case of lung patients. They're living longer. We have evolved
01:10:06.400
where we've been finding people that were previously radiated to the brain were having
01:10:09.920
cognitive issues years down the road. Not for the short term, they would tolerate it well,
01:10:14.200
but maybe they'd start to have more forgetfulness, an inability to remember numbers and names and
01:10:19.280
whatnot. And this was from whole brain radiation?
01:10:23.340
So we're talking about 30 gray to the whole brain given in 10 fractions of three gray each.
01:10:29.260
Three gray times 10 was a sort of a standard thing.
01:10:34.420
And that's to the brain. So it's a different story.
01:10:36.280
And just to be clear, do you need to use way more radiation because that's what you're
01:10:42.380
delivering to the brain? Is this an example of where the sieverts and the gray are very different
01:10:48.940
No. So the only difference between sieverts and gray in any patient is going to be whether
01:10:52.100
we're talking about dose in tissue or coming out of the machine. Basically the dose in air versus
01:10:56.820
dose in the patient. The biggest thing with brain tumors, yes, the bone certainly is going to
01:11:02.020
attenuate more dose. But what I'm talking about is actually 30 gray into the brain itself,
01:11:08.360
Doesn't that mean you need much more than 30 gray coming out of the machine?
01:11:12.840
It's not like they're wearing a football helmet or something. Yeah. Photons can still pretty much
01:11:16.460
go through everything. It's not metal. So it'll still go through. The dose is a little higher
01:11:20.340
and it gets to be like, for example, in a lung patient, it's more of an issue when you have
01:11:24.120
multiple different areas. You got bone, soft tissue, and air. In that situation, you have to
01:11:29.240
modulate the dose more. But in the case of a whole brain, it's been found, of course, that the
01:11:33.100
hippocampal dose is very much related to their cognitive deficits down the road. So now that we
01:11:39.200
have IMRT, which is a term I hadn't mentioned before, but that's basically intensity modulated
01:11:44.660
radiation therapy, which is also the magic behind allowing us to treat a prostate without burning the
01:11:49.180
bladder and the rectum. And the newest form of IMRT is called image-guided radiation therapy.
01:11:54.300
So you hear IGRT. Basically, those two terms go together. But by using IMRT, it's kind of like an
01:12:00.460
HDTV versus this 1960s black and white blurry set where we can treat with multiple small pixels and
01:12:07.180
high definition, so to speak. So now when we do a whole brain, if I have to do a whole brain for
01:12:11.720
multiple metastases, by using IMRT, I can literally carve the dose out. I can map out the hippocampus and
01:12:17.680
carve the dose out of there. So you see these two cold spots on the hippocampi and really have a
01:12:22.200
very low dose there while still treating the remainder of the brain parenchyma.
01:12:24.900
Are there other parts of the brain that you carve out and protect?
01:12:27.560
That's the main one. Of course, we are going to not necessarily completely carve out because when
01:12:31.380
you have multiple metastases, really the whole intracranial space is at risk. You have to cover
01:12:34.900
everything. So believe it or not, 30 gray sounds high to you, which it is. But for a glioblastoma,
01:12:39.940
we use 60 gray. Granted, that's not to the whole brain. That'll be to the, either if it's an
01:12:44.100
unresectable patient, it'll be the primary mass. And then we will give maybe 46 gray to
01:12:48.600
the peritumoral edema. But then the rest of the brain is getting much less, hopefully zero in many
01:12:53.540
cases. Do we know what the survival difference is for an unresectable glioblastoma with and without
01:13:01.640
radiation? It's certainly worse. There's, again, multiple confounding factors there because someone
01:13:06.900
who's unresectable probably has other negative issues as well. They have poor overall performance
01:13:11.360
status. They have neurologic deficits. Whatever the reason the surgeon can't operate, that makes
01:13:15.260
it worse. But yes, even then in that situation, you get probably, again, you're measuring survival
01:13:19.820
in weeks to months, but it's probably double with radiation than without. A lot of our GBMs though are
01:13:25.580
resected, hopefully fully resected in terms of at least radiographic, a post-op MRI not showing any
01:13:31.380
enhancement. If you have someone that's got a fully resected primary who's a younger patient with
01:13:35.880
not a lot of neurological deficit, they can live a couple of years actually.
01:13:42.280
That's the key question. I know you and I are both Rush fans. Neil Peart was lost to
01:13:46.320
GBM as well. And yeah, it's so many people that's taken away. But I think it just has
01:13:51.080
to do with the invasiveness of the fingers of the tissue in terms of even when you think
01:13:55.540
you've gotten the whole thing, there's microscopic fingers that are always on the periphery and
01:13:59.720
you can't just radiate it indiscriminating like you can other parts of the body because
01:14:03.040
you've got the brain there. There's always a fine line you're walking between causing,
01:14:07.320
say for example, necrosis of the brain versus letting the tumor recur. And so that's really
01:14:12.500
the number one issue. We do have a new tool now as far as radiation oncologists in terms
01:14:17.300
of treating CNS tumors, which is called proton therapy that you've probably heard about.
01:14:21.520
There's several centers in the country now. MD Anderson where I am in Houston has a huge
01:14:24.980
one. But with protons, you potentially can have the dose go into the brain to a certain depth
01:14:31.000
and not exit out the other way, like an x-ray would. X-rays are like light. It goes right
01:14:35.420
through you. You may have a decreasing dose, but it's kind of like a bullet. You got an exit wound
01:14:38.920
going out. With proton therapy, this is one of the areas where protons shine because you can
01:14:43.080
actually modulate what's called the Bragg peak of the physics of the protons to where it'll go at
01:14:47.840
certain depth and not go out the other way. So down the road, hopefully we'll start to see
01:14:52.240
improved survival. So far, it really hasn't shown to be a huge improvement, but there's less
01:14:56.120
integral dose to the rest of the brain. And it's especially important in pediatric patients where
01:15:00.400
you've got children with growing skull bones. And if you can avoid radiating the growing bone to cause
01:15:05.600
a deformity later on, that's huge. So proton therapy is one tool we have, but I wish I had an answer for
01:15:11.560
GBMs. That's going to be a game changer whenever that does happen. I find GBMs to be just such a
01:15:17.240
frightening type of cancer. And I do wonder if it's going to require some sort of injectable
01:15:22.240
immunotherapy or something. I think so. I just, you have to basically figure out a way to treat
01:15:27.660
the brain systemically. You have to mechanically overcome the blood brain barrier and come up with
01:15:33.380
some sort of systemic treatment for it. Okay. So today, how many patients are undergoing whole brain
01:15:39.880
radiation? Whole brain radiation is probably, to give you a number, I don't know what the absolute
01:15:45.400
number is, but it's probably 10% of what it was 20, 30 years ago. The original studies out of
01:15:51.300
Kentucky that Patchell had done in neurosurgery, everyone used to get whole brain radiation following
01:15:56.440
resection of the metastasis, or even if it was unresectable. And there was some good data back
01:16:00.700
then supporting that. But nowadays, rather than whole brain, you're usually going to do a focus
01:16:04.640
treatment just to a smaller area. And this is kind of a universal trend to less radiation dose
01:16:10.300
to a smaller volume. Same thing in lymphoma, you want to treat just the enlarged lymph node and not the
01:16:15.600
entire lymphatic axis. So it's the same idea where you're trying to minimize side effects.
01:16:20.180
So whole brain, we still use it in specific cases, like for example, small cell lung cancer.
01:16:25.260
Part of their regimen is going to be once the primary has been treated, if they have a complete
01:16:29.960
response in the thorax, prophylactic cranial radiation. Only for small cell. PCI, 20 gray,
01:16:35.880
five fractions, been done forever, shows an advantage to have lower disease.
01:16:42.020
It's a lot. I think it's probably 70, 80% reduction in CNS failures, because they all
01:16:48.440
fail there otherwise. Small cell, they just all do that. And at 20 gray, they really don't have
01:16:52.440
too many side effects. But again, of course, the caveat is always extensive stage small cell lung
01:16:56.880
patient isn't going to have a long-term survival, but at least they won't fail in the brain. It's a
01:17:02.040
I'm sorry, this is done with every small cell patient, no matter how early it's caught?
01:17:06.800
If they have a complete response to primary treatment, yes. Basically,
01:17:10.620
maybe there's some nuances, but for the most part.
01:17:15.240
So gamma knife is, instead of using a linear accelerator, it's actually using cobalt-60,
01:17:19.960
like I described earlier. But you have multiple small sources that can actually be used,
01:17:24.420
very high-resolution cobalt, essentially. So you're doing the same thing,
01:17:27.880
but instead of using a linear accelerator-based treatment, it's using cobalt.
01:17:32.280
There still are centers that use it. It still works very well for what it is,
01:17:34.880
but the focus is very narrow. There's a lot of children's hospitals and all that. I think
01:17:38.280
we're still using it. But the linear accelerator, which is abbreviated LINAC, the LINAC-based
01:17:42.720
stereotactic radiosurgery for the most part has taken over from that because it can do all the
01:17:47.340
same things and also have more flexibility to do more than just CNS. St. Jude's Hospital has a
01:17:53.320
fantastic PD-CNS program and they still have, well, it's been a while now, but they did have a
01:17:57.520
gamma knife last time I checked. Okay. So we've talked a lot about radiation. We've touched a
01:18:02.620
little bit on the idea of radiophobia, but maybe let's use that as a bridge to talking about using
01:18:07.940
radiation to enhance tissue as opposed to eradicate a subset of tissue. Does it stem from nuclear
01:18:16.860
accidents? Is that largely where radiophobia comes from?
01:18:20.500
I've done a deep dive into this this year, which goes along with all these benign cases that I'm
01:18:25.680
treating now. They're essentially arthritis tendonitis, which we'll talk about. And what's
01:18:29.660
really interesting is that this radiophobia is largely a US-based phenomenon because the first
01:18:36.220
cases, first of all, x-rays were discovered in 1895 by Rankin. In 1898, there was the first case
01:18:43.960
described of actually radiating both arthritis type things or ankylosing spondylitis or other
01:18:49.420
arthritis and also tumors. Even back then, we had no idea how it worked, but there were cases
01:18:54.000
pre-1900 that were already being used for that. And then in the subsequent now 120 plus years,
01:19:00.220
we have this divergence where Germany and the UK, all of Europe really, are using radiation routinely
01:19:05.620
for arthritis and tendinitis. But in the US, it seems to be a basic nuclear phobia, the Cold War,
01:19:10.940
like you mentioned. But another thing that's been talked about, there's a guy named Jason Bechta that
01:19:14.920
has a really good podcast on the subject. He's out of Vermont. Standard Oil, the Rockefellers and all
01:19:20.580
actually had a massive lobby group that were actually actively promoting oil over nuclear
01:19:26.720
power plants. The amount of spread went from just the energy industry into just the general zeitgeist
01:19:31.660
of the entire country. And so at that time, the radiophobia just caught on. And it was, of course,
01:19:37.380
bolstered by World War II and seeing what happened in Hiroshima and Nagasaki.
01:19:41.060
And then on top of that, you've probably heard about the radium dial workers. There was a movie,
01:19:45.520
it's actually called The Radium Girls. These are essentially women in the 1920s that were using
01:19:50.760
radioluminescent phosphorous paint to paint the watches.
01:19:55.020
Being a watch guy, you'll probably appreciate that. But that was the only source of illumination
01:19:58.220
they had. So in order to keep the brushes very fine, they were literally dipping it in the radium
01:20:02.720
paint. And then after each brush, they were licking the brush to keep the tip real fine. And so they
01:20:07.400
were ingesting bits of radium. So there were a number of cases where they ended up, the radium
01:20:12.040
is metabolized like calcium. So it was actually incorporating into the mandible and they were
01:20:16.820
getting osteoradionecrosis of the jaw and things like that. So all of these different phenomena
01:20:21.680
added together became a big deal because prior to that, people were using radiation for all kinds
01:20:26.260
of crazy things. It was in suntan lotions and waters. And there was something called vigoridine
01:20:32.220
that they were using for ED, topical salves that had radiation in them. It was literally
01:20:37.020
no end to it. And then when all this sequela started to come out that, hey, maybe this isn't
01:20:40.680
such a good idea, that's when things took off. But now that we look back, the reality of it is,
01:20:45.580
is that a lot of that was really overblown, even so much so that those radium dial painters,
01:20:50.020
which we hear about this from day one in our residency training, there was only a small percentage,
01:20:54.360
like I think 50 out of 1500 roughly, that actually had toxic sequela. So most of them didn't.
01:21:00.120
Is there a way to quantify how much exposure they had to radiation?
01:21:03.160
And that's the thing, you know, they've licked different ways, but there have been some basic
01:21:06.300
ideas. It was, again, we're talking about at that era, it was probably a couple of
01:21:10.120
millisieverts to that particular area, but it was daily for decades. And so part of the reason why,
01:21:16.100
if you actually look at the numbers, it was probably a super high exposure, but when you
01:21:19.140
spread that out over such a long period of time, that's sort of the general trend. Like I mentioned
01:21:22.760
earlier, it's not just the dose, it's the dose over time. The denominator matters a lot. And so
01:21:27.720
that's why most of them actually did very well. They even used to use radium internal nasal
01:21:32.100
applications in the 19, I guess, 1920s to 1940s, essentially a radiation equivalent of a tonsillectomy
01:21:38.780
or adenoidectomy. And it was done in something like a half million to 2 million children in the
01:21:44.360
U.S. and even in the armed forces. It was done routinely back then. And there's been very few
01:21:49.020
adverse sequela that were reported. I don't even know what the dose was, but it was high.
01:21:52.060
Right. So there's a lot of cases where the exposure based on our 50 millisievert rule we
01:21:56.640
talked about would just make people fall out of their chair. The actual reality of it is,
01:22:00.940
is that many times the actual end results aren't as bad as we had expected.
01:22:05.400
Again, hearing you say this, Sanjay, the listeners are going to be thinking,
01:22:10.440
Because we're all so brainwashed into believing that radiation is horrible.
01:22:17.940
Right. I can tell you so many stories. I got patients who I've had to treat. I had actually
01:22:21.640
had a guy who was involved in nuclear testing at Los Alamos in the 1940s. He's passed away now,
01:22:27.280
but I saw him in his 80s. So this was in the early 2000s. This was 60 years after that. They had very
01:22:33.320
little monitoring back then, but he was close enough to feel the heat from a thermonuclear bomb.
01:22:38.780
And by the time I saw him, he had had thyroid cancer, as you would expect. He'd had one or two
01:22:43.260
lymphomas. I think I ended up treating his prostate. So he'd had at least four or five
01:22:46.820
different malignancies, but the guy was as functional as most 80-year-olds are. The guy
01:22:50.400
was still walking and talking and doing just fine. And it actually seems that when you look at the
01:22:54.960
population studies that were done outside the blast at Hiroshima and Nagasaki, when, of course,
01:22:59.460
the initial concentration, everyone dies from the thermonuclear energy. But as you get several miles
01:23:04.060
out, not only are the cancer rates actually roughly the same as the background, you actually see,
01:23:09.760
evidence of hormesis where you have some patients in whom, or maybe not hormesis, but some sort of
01:23:14.140
radio protection where you actually have lower rates of leukemia and thyroid cancer when you get
01:23:18.260
a few miles farther out than you did in the general population. So it's all very much dose-dependent,
01:23:23.340
time-dependent. But I think the human body, we're evolved really to handle this to a larger degree
01:23:28.900
than we realize because, again, mammalian DNA, we came from the background of the animal kingdom where
01:23:34.040
there was tons of exposure from natural cosmic rays and whatnot. And then our predecessors had
01:23:39.640
to be able to survive. Our DNA had to be somewhat resilient in order to get to this point. I think
01:23:44.140
it's more resilient than a lot of people give it credit for.
01:23:47.220
So this first came up maybe a year or two ago when I was lamenting, it must've been two years ago,
01:23:53.080
I guess, because I was kind of lamenting my Achilles tendon, which I wouldn't say it was injured.
01:23:58.420
I just had a little bit of tendonitis. It was just bugging me a little bit.
01:24:04.200
And so it was through that discussion that we got into what we're talking about now,
01:24:07.860
which seemed crazy. I just decided I didn't feel like driving to Houston all the time to undergo
01:24:12.320
therapy and my Achilles is fine now. I just did sort of standard therapy. But I've sent a few
01:24:17.240
patients to you who have had similar injuries, both high hamstring tendinopathies, Achilles
01:24:23.560
tendinopathies. So talk a little bit about this idea. How prevalent is this type of treatment in
01:24:30.860
So prior to probably 1970 or maybe 1980, it was very prevalent even in the US. It was very widely done.
01:24:37.200
Everyone, I talk to them about it now, it sounds like I'm doing something experimental and radical.
01:24:41.860
But if you go over to Germany, again, going back to ankylosing spondylitis papers in 1898,
01:24:47.620
they do something like I hear between 20 and 50,000 patients a year in Germany. It's mostly
01:24:53.340
observational studies. There's very few randomized trials, but low dose radiation for tendonitis,
01:24:59.580
osteoarthritis, plantar fasciitis, all the itities you can think of, bursitis.
01:25:04.400
A low dose of radiation has a similar anti-inflammatory effect to what you would
01:25:10.580
So now we're talking about very low dose, meaning 50 centigray or 50 rads given six times over two
01:25:18.160
weeks. So three gray, 0.5 times six is three gray to the affected joint using a very low energy
01:25:25.320
machine. So this is especially in the case of someone who's got a hand, you're talking about
01:25:30.060
Sorry, let me just make sure I got that straight. You were giving 40 gray total to a breast.
01:25:38.200
And now for the Achilles, you're giving how much?
01:25:41.520
Three gray, six fractions of half a gray each. So all six fractions combined is about the dose of
01:25:49.000
one fraction for a typical cancer. That'll give you the idea. And giving it in a superficial fashion
01:25:55.040
where especially if it's a hand, you only have a couple of centimeters of thickness. So we use what's
01:25:58.600
called electron beam therapy. The same linear accelerator when the electrons go and hit the
01:26:03.660
tungsten target and make photons, if you remove the tungsten target, you just get direct electrons.
01:26:08.480
And electron energy can be modulated to where you can treat a superficial skin cancer. You can treat
01:26:12.780
a knuckle. I can treat a temple squamous cell and not go into the brain. In the old days, before they
01:26:18.260
had linear accelerators, I told you this goes back to the turn of the previous century, they had
01:26:22.000
orthovoltage machines. And these basically created kilovoltage x-rays, not the megavoltage
01:26:27.160
x-rays we use now. And all they could do was superficial stuff back then. And that's where
01:26:31.820
it works very well. The dosage has changed tremendously, but these days, the biggest data
01:26:36.140
comes out of Germany, half a gray, three times a week, Monday, Wednesday, Friday for two weeks,
01:26:40.840
just to the affected joint. And it has an anti-inflammatory effect very similar to either
01:26:49.440
Two weeks. Monday, Wednesday, Friday, six treatments. And the protocol is what we typically
01:26:54.140
follow. The German protocol is to wait 12 weeks. And you usually see, depending on the
01:26:58.900
joint, somewhere between a 60 and 80% success rate where the pain is, if not zero, at least
01:27:04.740
markedly decreased. And then after 12 weeks, the German protocol allows for a retreatment.
01:27:09.360
And at that point, you get up to 90 plus percent success in terms of reducing pain.
01:27:14.880
Arthritis, tendinitis, bursitis, plantar fasciitis is a really big one now that we're doing a
01:27:21.080
bunch of. I've done probably close to 70 cases across the board just this last year.
01:27:24.620
Which is kind of remarkable because anybody who's had it, you know, I had it once back
01:27:30.280
Did you get it treated or was it just, did it just resolve?
01:27:32.940
I mean, I just went to PT and rolled on golf balls and did the usual thing, but it took
01:27:39.840
So you're saying of the patients that are coming to see you with plantar fasciitis, how
01:27:44.400
many of these patients, how long have they been hurting, first of all?
01:27:47.600
Many times for years. And in fact, my biggest cohort recently, which is still relatively
01:27:51.780
new, I haven't done thousands of patients. Like I can speak from decades of experience
01:27:55.720
with cancer. We're talking about dozens to hundreds. A couple of surgeons that were having
01:27:59.380
trouble standing and operating. They literally couldn't perform their normal duties. Six treatments
01:28:04.780
to the fascia and they're walking like nothing ever happened.
01:28:10.520
In the case of plantar fasciitis, it was almost immediate. Within a week. I have other cases,
01:28:15.880
especially when we do like knee arthritis, if there's a lot more pathology going on in
01:28:20.080
a knee. I treated my own Achilles, which I can tell you about. It took two months or so.
01:28:24.620
I was almost wondering if it was going to work or not. I was my own first patient. Before
01:28:27.460
I offered to anybody, I treated my own Achilles.
01:28:29.640
Physician, heal thyself, right? And so I literally jumped on the table because a colleague of mine
01:28:34.340
had posted about it that he did his, he's a radiation oncologist in Florida. He tried
01:28:37.880
it out. And so I was like, you know, I have the machine. I know this should work in theory.
01:28:41.740
We were just never taught about it in residency. And I look at all the German data. There's tons
01:28:45.040
of it. It's like, why do we not do more of this? And sure enough, I'm actually my own
01:28:48.660
personal case control study because I did steroids and PRP in my left Achilles. And then later on
01:28:53.660
this past year, did the right side with only radiation and no steroids. And now I'm walking
01:29:00.540
No, no, actually I didn't. The PRP actually finally did. So I had two cortisone shots and PRP in
01:29:05.140
the left. And then a year later, radiated the right. Both of them are holding up pretty well
01:29:10.720
Got it. The other area that is of huge interest for me at least is the very, very high hamstring
01:29:17.060
tendinopathies. So that ischial tuberosity pain, very, very common for runners. Seems to be
01:29:24.920
anecdotally much more common in women than men based on pelvic anatomy.
01:29:28.300
I've only treated women for some reason with that. And they've all had tremendous results.
01:29:32.320
It's still the same protocol. It's the three gray over six treatments over two weeks.
01:29:36.600
Exactly. For any type of an arthritis, you're essentially lysing all the macrophages and
01:29:41.500
you're eliminating that cytokine storm that would have normally resulted. It's very similar
01:29:45.420
to what cortisone does, but the difference is it seems to be based on the studies we've
01:29:48.700
seen is much longer lasting than a cortisone shot. Not to mention the fact that you're not
01:29:52.260
necessarily violating the capsule. And in the case of an Achilles tendon, you run the risk
01:29:56.440
of rupturing it with multiple injections. So totally non-invasive. You just get up on the
01:30:00.560
table. Most of my patients, they go right back to whatever they were doing. And many
01:30:03.240
of them are actually quite athletic and they don't take any breaks during treatment. They
01:30:07.020
just do what they do. They're still working out.
01:30:09.460
Is there any literature looking at this for spine injuries? By injuries, let me be clear
01:30:15.500
what I mean. So when you think of all the times that people are getting spinal epidurals
01:30:20.720
for irritation of spinal nerves, herniated discs, things of that nature, is there any reason
01:30:26.580
to believe this could have any efficacy there if indeed there's some efficacy, which there
01:30:30.680
clearly is due to spinal injections or epidural injections?
01:30:34.180
There is some data for spinal osteoarthritis specifically. It's less robust than all the
01:30:39.740
extremities. I've actually done a few cases and it's actually worked quite well. Medicare
01:30:43.820
actually does reimburse for these things. The issue with the spine is it's such a multifactorial
01:30:48.880
area where if you've got a nerve root compression or a disc issue, I can't fix that part of it.
01:30:54.260
But there is limited data that I've seen out of Europe that did show some degree of relief,
01:30:58.800
but it's not the 80 to 90 percent that we quote for the extremities. It's probably half
01:31:03.340
Interesting. And do you think it's because of patient selection? Like if you knew you were
01:31:07.660
dealing with a facet arthropathy, that should in theory respond well.
01:31:12.260
It should. And it does. I've done a few of those. SI joints seem to respond quite well,
01:31:16.300
and that's in the literature. That's included. So hips, SI joint, lumbar spine, those sorts
01:31:21.220
of things. They are described. They're just not as routinely treated. There's not as the level of
01:31:25.880
experience that we do have with everything else. But your ability to center the beam
01:31:31.040
is remarkable. You're using the same high fidelity equipment you're using for Radonc.
01:31:38.720
Well, you could, but that's exactly what you don't want to do because you're basically trying
01:31:41.900
to eliminate all the macrophages in the region. So you're actually better off treating larger fields.
01:31:46.380
So it's the exact opposite of what we do with cancer therapy. And because the dose is so low,
01:31:51.420
you're not really gaining anything by being too cute with the small fields. You actually want to
01:31:55.320
treat the region. It's like almost like an abscopal effect for the whole area.
01:31:58.840
So if you're treating somebody that comes to you and they've got an Achilles tendinopathy,
01:32:03.340
usually there's a point of maximum tenderness, but it usually hurts up and down the whole Achilles.
01:32:08.580
How do you position the beam? And are you literally hitting from mid calf down to heel?
01:32:14.320
From the insertion in the gap. In my case, part of the gap, the inferior gastroc was painful too.
01:32:19.780
So I treated that entire region. The field was probably about that long,
01:32:23.020
all the way down to the calcaneal insertion and even onto a little bit of the plantar surface of
01:32:27.500
the heel. Because again, when you're talking about these super low doses of radiation,
01:32:32.100
if it was a sarcoma of that area, I'd be treating a tiny little area. But over here,
01:32:35.720
we want to treat the whole region. Most radiation oncologists, we talk to their experience
01:32:39.640
treating an extremity. It's usually for a sarcoma. So that's a whole different ballgame where
01:32:43.700
you're giving 60 grade to someone who's had a sarcoma in their leg or something. And you have
01:32:48.180
to worry about things like edema. You can have lymphedema of the distal extremity if you've
01:32:53.180
radiated the whole circumference of a leg or something like that. But with these low doses,
01:32:57.300
it doesn't affect any of that. So you do treat large fields. So it'll be from the insertion of
01:33:01.740
the Achilles all the way down. If it's a plantar fascia, the entire plantar surface of the foot.
01:33:06.580
Another thing that we see a lot, which is not arthritis, is diputerins, contracture,
01:33:10.580
and also the foot equivalent, which is leader hose disease. I had to look that one up. That was a
01:33:15.300
trivia question. But it's essentially palmar or plantar fibrosis. And so radiation works well
01:33:21.400
there as well. Very well documented. And that requires a higher dose though. You're talking about
01:33:26.280
three gray per fraction, five fractions, and then you do it again after a few weeks.
01:33:33.600
Yeah. Almost palliative cancer, not a high dose. But again, that's for fibrosis.
01:33:38.040
And keloids, it works very well to get teenagers with big old golf balls hanging off their ear
01:33:43.120
after getting their ear pierced and things like that. And so again, you're treating the fibroblast.
01:33:46.980
In that case, you use four gray times three treatments of 12 gray, relatively large dose
01:33:55.580
I've seen, obviously, patients with debilitating keloids. What does it look like after the treatment?
01:34:01.600
So the treatment has to be adjuvant after a surgical resection. If you just radiate an
01:34:05.920
intact keloid, it's not going anywhere. Because you don't have the DNA mechanisms of a weak
01:34:10.840
cancer cell that can be wiped out. So it's kind of like doing a lumpectomy.
01:34:14.200
But obviously, if the surgeon just did the resection, the keloid's coming right back.
01:34:17.900
The fibroblasts go crazy and they roar right back. So in order to do it right, a lot of
01:34:22.300
people do it and they have multiply recurrent keloids even after treatment. You have to do
01:34:26.000
the first treatment the same day as surgery. So you're just not letting those fibroblasts get
01:34:29.900
a chance to have any sort of a foothold. So I would literally arrange it with the dermatologist
01:34:33.580
to do the resection, send them straight to me. So we get the first dose in that day.
01:34:37.560
And ultimately, the cosmetic outcome is as good as if they didn't have radiation.
01:34:41.060
You'll see the scar wherever it is. We get sometimes kids that have had acne scars all
01:34:45.200
over their chest that have these bumps everywhere and they were all resected flat. And you radiate
01:34:49.080
them, they just stay flat. You don't see any sort of dermatitis from radiation.
01:34:52.700
I think what's amazing to me is I just think there's too many people that don't know this.
01:34:56.180
I think there's too many people that are walking around suffering either from something
01:35:00.600
that's cosmetically upsetting, like a huge keloid, especially on a visible part of their
01:35:05.060
body. Obviously, everybody listening can relate to some nagging injury, tennis elbow, golfer's
01:35:10.400
elbow, Achilles tendinopathy, hamstring tendinopathy. These things nag for years at times.
01:35:18.260
The data was showing some like one in seven people in the country are afflicted and the
01:35:22.200
socioeconomic costs are massive. And there's also, you know, going to your whole quality of life
01:35:27.600
and longevity bias. I mean, we're talking about something that can really affect someone's ability
01:35:31.260
to exercise at all, and it can lead to exacerbation of other medical problems.
01:35:35.920
You know, I was very encouraged to hear you say a second ago that Medicare is covering some
01:35:40.340
And private insurance too, yes. For the most part. Now, a lot of times, because it's relatively
01:35:43.560
new, I'll have to get on there and do a peer-to-peer with the company, but I've had no rejections
01:35:47.400
at all. Even for the spinal ones, which are a little bit, there's less robust data,
01:35:52.560
So, I think the question is, do we need more radiation oncologists? Because how are you
01:35:59.220
making room in your practice to treat these patients when your cancer patients are probably
01:36:06.180
That's a big reason why it hasn't caught on. I think there's a component of just,
01:36:09.920
you've got eight hours or 12 hours a day that the linear accelerator can run. We're busy with that.
01:36:14.540
But one of the things is that because, unless it's a deep hip or something, for most of the
01:36:18.780
superficial, for all the other joints, you can use one of those old-style orthovoltage machines
01:36:23.120
that I mentioned earlier, like what they use in Europe. They still sell those here. There's a
01:36:26.780
company called Extrol that still makes them, and they're perfectly acceptable for all the joint
01:36:31.540
stuff, except for the very deep ones, like maybe a SI or a hip joint. But you could have a small
01:36:36.740
center set up, and those types of machines don't even require the shielding because the energy of
01:36:40.680
the photons is very, very low. It's highly underutilized at this point, and the Europeans have shown us
01:36:46.300
the way. It clearly works, and America just has to catch up.
01:36:50.240
Yeah, this is definitely an area where we are way far behind.
01:36:53.500
But it's truly exciting. I mean, I love treating cancer patients. It's really personally very
01:36:57.340
rewarding to tell someone that they're NED, there's no evidence of cancer in their body anymore,
01:37:01.640
their PSA is low, their mammograms look good. That's what's kept me going this long. But the
01:37:06.120
amount of immediate relief we're seeing from all these inflammatory conditions, right away,
01:37:11.080
it's a night and day. Patients come in one day, they can't grip a doorknob or lift a gallon of milk
01:37:15.700
out of their fridge. And after six treatments, they can, and they're just, they think you hung
01:37:19.380
the moon. It's an amazing thing. I'm hopeful that people listening to this,
01:37:24.400
so if there's a million people listening to us have this discussion, and one in seven of them,
01:37:29.920
let's just say one in 10 of them, at some point in the next couple of years are going to experience
01:37:34.540
the type of injury that would benefit from this. How can they go about finding, you know,
01:37:39.320
they can't all come to Houston to see you. I'm trying to get you to move to Austin. But regardless
01:37:42.860
of where you end up, they can't all come and see you.
01:37:45.960
You already said the answer. I'm just going to move to Austin. We're just going to do this full
01:37:48.100
time and drive cars on the weekends. No, but seriously, there's an uphill battle because
01:37:53.120
as I've been going out and trying to get the medical community in Houston aware of it,
01:37:56.880
you have a lot of pushback because number one, you've got orthopedic surgeons, podiatrists,
01:38:01.840
hand surgeons who are looking at this like, number one, what are you doing? What are you talking?
01:38:05.180
They look at me like I'm crazy. And number two is like, even if this actually works,
01:38:08.720
the concern is when someone's got maybe a knee arthritis, it's been nagging them and maybe
01:38:12.800
they're going to need a total knee at some point. Their concern is, wait a minute, is this taking
01:38:16.320
surgery off the table? Which it's not by the way, because it's such a low dose. There's been plenty
01:38:20.920
of cases of surgery after the radiation. It's not an issue. Or you're taking away from like when you
01:38:26.040
had your plantar fasciitis, I'm sure the podiatrist build something for when they do those extra
01:38:30.060
corporeal shock treatments and steroids and whatever it is. It's a different paradigm that would
01:38:35.660
potentially be taking away. A lot of doctors are very negative about it. Most of them at this point
01:38:40.100
are very negative, but I think that tide is going to turn just like anything else. It's just going
01:38:44.300
to take a lot of education, a lot of time, a lot of talks like this. Well, I think at the end of the
01:38:48.060
day, look, I don't think patients will have any patience for turf wars. Yes, that's true.
01:38:53.100
And so if I'm a patient, every doctor needs to be a fiduciary. They need to put my interest ahead of
01:38:59.880
their interest. And what's interesting is that I think you can have your cake and eat it too.
01:39:03.800
The reason I say that is many times this is an adjuvant for other things. So if you've got a
01:39:08.080
podiatrist that's doing all these PRPs and the other things, I'm actually looking at starting a
01:39:11.840
protocol. I just treated a nurse in Houston who's a NP who does stem cells off label, but she does
01:39:16.860
them routinely, has quite a big practice. We're going to look at maybe you can do radiation with
01:39:21.180
adjuvant stem cell treatment because it's such a low dose. This may be the sort of combined modality
01:39:25.780
thing down the road that we haven't really approached where there may be options to do other things
01:39:29.700
still. But again, I mean, for Medicare to improve something is a huge bar. How are you getting
01:39:35.300
Medicare to improve this? Are they basically acknowledging that, well, hey, if Europe's
01:39:39.320
been doing this for a hundred years and it's working, like what's their bar?
01:39:41.860
That's what it looks like. You know, I've got the C61, which is the ICD code for prostate cancer,
01:39:46.340
which is in most of my patients. We've got the osteoarthritis codes. Now they just go right
01:39:49.740
through typically without any sort of a problem. Some of the private insurances, you have to get on a
01:39:54.520
peer-to-peer call, but all I literally will do is quote them a couple of the German studies.
01:39:58.940
Unfortunately, we got a little bit of a setback because there's only two randomized clinical
01:40:03.080
trials that are both heavily underpowered, poorly run studies, just not well done. So that's been a
01:40:07.960
little bit of a setback. And the randomized data may never come just because of the nature of this
01:40:11.900
sort of thing. But having said that, that's not the obstacle anymore. It's really just public
01:40:16.660
awareness. And like you said, just like a guy that doesn't want a radical prostatectomy and wants
01:40:20.700
radiation therapy for his prostate, he's got to be his own advocate. And the data is out
01:40:24.460
there. The information is out there. There's a couple of big Facebook groups and one is only
01:40:28.220
Diputrins patients. And they literally will post up there, I've got this big nodule. What do I do?
01:40:32.440
My surgeon wants to cut on me. And so there's actually a whole network now. So there's a lot
01:40:36.180
more of that education going on. They've got big PDF files of doctors all over the US that will do
01:40:41.260
Diputrins radiation. So Diputrins is a little bit more commonly accepted, but as I'm slowly talking to
01:40:46.320
these folks, they're going to migrate into their arthritis space as well. So I think it'll come
01:40:50.820
and the general public has nothing but great positive outcomes from this.
01:40:55.240
Do we have a sense of the durability of this? So for example, I have a little bit of osteoarthritis
01:41:00.300
at my AC joint on the right. It barely bothers me, but every once in a while, if I'm doing something
01:41:06.460
really violent overhead, reaching for something, or I play a ton of football with my son, it'll bug me
01:41:12.080
for like three weeks. I'll take a little bit of Advil. It's fine. If I did a treatment there,
01:41:17.120
would it be done or am I doing this treatment annually? How would it work?
01:41:20.820
There's a lot of variability there, depending on what the actual anatomy that's causing it. If
01:41:25.060
it's literally just a straight up osteoarthritis case with no physical structural issue, I've seen
01:41:30.220
cases. Now again, I've only been doing this about a year, so I don't have the 25 years of experience
01:41:34.280
I do with cancer, but I've talked to, there's a couple of doctors who do this routinely. They've
01:41:38.360
been doing it for 20 years in LA. One of them treated his own neck, shoulder, and spine. I think
01:41:42.600
he's at 15 years out, anecdotal obviously, but never had to retreat himself. Typically the German
01:41:48.220
studies allow for two treatment, two retreatments. Because the dose is so low radiobiologically,
01:41:53.640
I don't see any reason why you couldn't do it. I don't know about annually, but maybe every few
01:41:57.860
years or something like that. But there seems to be a fair bit of data that a lot of patients who
01:42:02.220
don't have other struck, like a knee that's bone on bone, it might only last a month or may not even
01:42:06.700
work. But for the other ones, like the hands and all, it seems like it's certainly longer lasting
01:42:10.880
than any sort of cortisone shot. But I think months are very reasonable and probably years for most
01:42:16.280
people. Now, what about non-osteoarthritis, like rheumatoid arthritis and things like that? Is there
01:42:21.280
any reason to believe that this could help with the debilitating injuries that those patients
01:42:25.240
experience? So I've done three cases of rheumatoid arthritis and one guy that had a Gaudi arthritis as
01:42:31.020
well. Because again, it's a systemic disease. I'm not going to pretend to be able to cure that with a
01:42:34.560
local treatment. But to a single knuckle that's driving them nuts, it's still an inflammatory
01:42:38.660
process. And yes, it works great for that. So if a patient has rheumatoid arthritis, where they're
01:42:44.360
really experiencing a lot of deformation in the hands, you think you can help that patient with the
01:42:50.280
local part of it? Yes. It won't reduce the deformation necessarily because a lot of that is
01:42:54.360
longstanding. But if they were treated early enough in the course of the disease? Yes. I think
01:42:58.100
there's no strong data to support that, but I don't see why it wouldn't work personally. And it
01:43:02.500
definitely, from a purely palliative standpoint, just to reduce pain, it does work. You have to manage
01:43:07.780
their expectations. What are some other examples of where this could be used, at least in your
01:43:13.220
experience so far, in terms of reducing reliance on NSAIDs or opioids or other things like that?
01:43:18.560
Tennis elbows become a big one, doing several of those. How far down the arm do you irradiate?
01:43:23.580
I base it on where the patient, if they palpate, and if they're getting pain down into the brachial
01:43:27.320
radialis, and if it's radiating further down, I'll treat a larger field. Because again, there's no
01:43:31.200
reason not to. Bigger fields are better. No need to be. And again, it's just six. Three gray.
01:43:35.260
Three gray. Three gray. And again, that's three gray locally. It's to an area where there's no
01:43:39.920
vital organs nearby. The total body dose is negligible. It's like getting a CAT scan initially
01:43:44.080
for the rest of the body. So I would treat definitely the joint capsule and a little bit
01:43:48.460
of the distal humerus and the proximal radius and whatever else. But if it's hurting larger,
01:43:53.060
I'll just treat a larger field. In that case, we use opposed lateral beam. So the patient will just
01:43:57.540
lay there. The beam will come in from one side and rotate around from the other side, and we treat them
01:44:01.220
both. Because that way, we get the same type of homogenous dose we do with our cancer
01:44:04.860
patients. I've actually done several piano players that have dequeur veins, tenosynovitis in their
01:44:10.140
wrist. Because when you're stretching to play those notes, I'm a musician as well. All my musician
01:44:14.240
friends are coming to me, the wrist pain is going away very quickly. My biggest patient cohorts so
01:44:19.580
far are former patients because they don't have radiophobia. They're like, I've been through 80
01:44:23.520
grade in my prostate. This is a joke. I'm bringing my wife with me. And half the times the wives sit
01:44:28.280
there for their daily treatment anyway, and they start chatting in the lobby. So we do the wife's hand
01:44:32.320
the same time we're doing the husband's prostate. And for the most part, the hands, the wrist, the
01:44:36.080
elbows, it's very rapid. In the case of the tendinitis, like my Achilles, it was a couple
01:44:40.360
of months, but that's not outside of the window of what we've been conditioned to expect from all
01:44:44.780
the German studies. So it can be not as immediate of a relief as a steroid shot, but it does seem to
01:44:50.140
be more durable. Yeah. We failed to mention at the outset that you're also a remarkable musician.
01:44:55.800
How much do you still play the drums? I got a couple of, actually a couple of doctor buddies. We get
01:44:59.960
together and jam every week or two. And one of them is actually a guy now who's actually got his
01:45:03.980
own YouTube channel and Spotify. And he was actually a professional musician before becoming a
01:45:07.900
cardiologist. So we may actually start touring again. But back in the day, we had a full doctor
01:45:12.000
band, a full seventies rock cover band called Ultrasound. Those are the good old days. We used to
01:45:17.800
play, you know, Journey and Rush and Led Zeppelin all day long. Yeah. I was commenting recently on a
01:45:22.640
podcast how much I regret not seeing Rush during their last tour. Again, because of a GBM, tie it back into
01:45:29.780
what we're doing here. Neil was a genius. So greatest drummer of all time. Are you going with
01:45:34.100
Neil? Are you going with Bonham? Neither, because I went to college here at UT and that opened my
01:45:39.520
entire eyes up to the world of jazz. So the jazz drummers can all drum circles around those guys in
01:45:45.380
terms of pure technical ability. But yeah, feel, rhythm, not necessarily being able to wow people the
01:45:51.700
way the jazz guys can, but yeah, Neil and Bonham are both right up there on the rock side of things.
01:45:55.880
Would you put them at the top of the rock list?
01:45:57.980
I would put Neil first. I'm just partial to Rush. And a lot of that has to do with their music,
01:46:02.540
not necessarily. Now, Neil was obviously an innovator, but as a 16 year old, I'm sitting
01:46:06.200
there trying to imitate every single note on his drum solos, everything like that. Neil,
01:46:10.520
number one, but Bonham and the new generation rock guys are incredible. The guys that grew up with
01:46:15.020
Neil as an inspiration, you've got 12 year olds who can do this stuff in their sleep. And then all
01:46:19.880
these math metal bands, you got dream theater and things like animals as leaders. Some of
01:46:25.860
these guys are doing things. I pride myself as a drummer on being able to analyze the music really
01:46:29.980
well. It's getting to the point where it's almost more math than music. Like it's so intricate,
01:46:34.720
the modulation of the time signatures and things like that. It's actually getting beyond where
01:46:38.560
even I'm having trouble understanding it now. But these guys-
01:46:40.900
And can you appreciate it from an auditory perspective? Does it get too technical where
01:46:47.640
That's a fine line because when you think about it, music is just math with emotion added in.
01:46:52.480
And it gets to a point where some of it is not appreciable anymore, at least not to me. Some
01:46:56.000
of these guys love it. But that's where the jazz side comes in, where it's all about feel. But even
01:47:00.420
the jazz guys will be extremely talented in terms of their ability to feel the beat and have it be
01:47:06.560
pleasurable to the ear, but they're doing such intricate things. And when you can balance those two
01:47:11.160
things out, that's heaven as far as I'm concerned. When you can have the emotional side and also
01:47:14.740
be technically challenging and not just playing a straightforward- The straightforward stuff is
01:47:18.880
great too, but it gets a little bit tedious sometimes.
01:47:26.240
Yeah, yeah, yeah. Which by the way, not to crap all over it, I ended up doing it because at the last
01:47:31.120
second I got a phone call from my driving coach and he was like, hey, I'm doing this AMG driving
01:47:35.660
school and they got an extra spot in the advanced drift school. Do you want to come? But I'd already been
01:47:40.380
to the Drift Academy with my friend, Josh Robinson. I was like, yeah, sure, I'll go.
01:47:44.120
And I was like, boy, this is the last time I ever do one of these schools.
01:47:51.940
Yeah. If you want to learn how to drift, you go to the Texas Drift Academy.
01:47:55.040
I want to go to Minnesota with him and do that ice class.
01:47:58.640
I don't know if I'll be able to make it or not. I'm trying to.
01:48:02.920
Well, I knew who you were because I've been a member. I've been a follower for years. I was like,
01:48:06.040
that's Peter T over there. So luckily we got paired up in the same group and that's kind of where it
01:48:10.120
started. It was totally random. I was actually just, it was a last minute thing. That was actually
01:48:13.300
a level two. So I was like, you hadn't done the level one.
01:48:15.980
So I was like, man, how did this guy get in here without even doing the level one?
01:48:19.280
So having done that, I agree, especially those cars with the automatic transmissions and the
01:48:25.540
Yeah. Yeah. You've been kind of a car nerd your whole life. What is it about cars that has you
01:48:31.920
You know, I think whenever anybody asks me that, I kind of think about it in terms of
01:48:35.980
every three or four year old boy is enamored by cars, but normal people just grow out of it.
01:48:40.420
And some of us never do. My dad certainly liked cars. He taught me how to change my oil and whatnot,
01:48:44.520
but he wasn't a fanatic like I am. So it just kind of started there. And then it got to the point
01:48:48.740
where like, my parents will tell you the story. I was that four year old who could tell you
01:48:52.060
at a car driving by, if it was an Oldsmobile that had Cadillac hubcaps on it, like, how the hell
01:48:56.340
does this kid know this thing? Yeah. I don't know where it just kind of clicked over the years. It was
01:48:59.880
always just a nice release. I guess being a mechanically oriented type person, I think if I didn't do
01:49:04.140
medicine, I would have done engineering, which is why it's so impressive. What did you study in
01:49:06.540
college? I was actually biology. I did a BA with art. So I did a lot of jazz studies at UT. So I was a
01:49:11.720
music guy. Engineering just seemed fascinating to me. You know, I was always interested in medicine
01:49:16.840
from day one, but I think that really the mechanical side of things, like knowing that every car's five
01:49:21.600
gear ratios and what their torque converter lockup is and what their horsepower and torque is,
01:49:26.400
it's just- And what posters of cars did you have on your wall?
01:49:29.380
The same as everybody. Actually, no, because everyone had a Countach, right? I never had a Countach.
01:49:33.360
See, I had a Countach. What did you have? I mean, they're cool. I would have like a
01:49:36.540
Callaway Corvette, Miami Vice Testarossa, 928, which I'm almost done with my old 928,
01:49:43.160
getting it back on the road. More of the domestic stuff and the stuff that's more attainable,
01:49:46.980
Fox Body Mustangs, the five liter Mustangs of that era are really cool. C4 Corvettes back in that
01:49:52.700
era when they were state of the art. I mean, I loved watching Knight Rider. So I thought Pontiac Firebirds
01:49:56.840
were super cool. It's funny. I just bought my youngest, his first Lamborghini
01:50:03.200
poster. He's mostly got sports posters on his walls, which is great. But I was like,
01:50:08.000
you got to have like a Lamborghini poster. So let's go pick one out. So we scrolled Etsy
01:50:13.100
for hours because I wanted to figure out what his taste was. Did he want to go retro? Did
01:50:18.200
he want like a Countach? But in the end, I think we went with, I can't even remember now. Actually,
01:50:23.820
we just ordered it. I think we went with an Urucan.
01:50:27.620
Oh yeah. It was going to be an Aventador or an Urucan. But get the color right and get
01:50:36.040
I have. It's one of those don't meet your heroes kind of things. It's cool,
01:50:39.800
but it's kind of a POS too. The bar has moved a long way since then. It's for the experience.
01:50:44.960
I mean, you clearly don't expect it to perform like a modern car, but even if you
01:50:48.660
judge it for what it was in the eighties, is it still not enjoyable?
01:50:53.740
It's enjoyable because of the eighties campiness in retrospect, but even compared to its contemporaries,
01:50:59.660
you look at an eighties 928 Porsche or even a Testarossa, those cars are beautifully driving,
01:51:04.780
you know, long distance cruisers, super comfortable, compliant suspensions. You got good ergonomics
01:51:09.340
and the Countach is so awesome because it has none of that. It's awesomely bad.
01:51:13.060
Yeah. Yeah. I've driven a Testarossa. Have you ever driven an F40?
01:51:16.400
I have not. I would love to have ridden in one, but I haven't driven one. It's a race car.
01:51:20.580
You're basically just sitting on the ground with a carbon tub around you.
01:51:23.720
So if you could have three road cars, but you can't sell them, you're not making the decision
01:51:31.020
based on economics. What are the three you want? Three road cars, not daily drivers.
01:51:36.400
Are we talking about just three cars that's all you can have in your garage? No, no, no, no.
01:51:39.440
These are your three grail cars. Okay. I would probably say, man, there's too many to choose from,
01:51:45.160
but to go with, it's going to sound like a cliche, but McLaren F1. I mean, how do you
01:51:49.040
not pick that? If I could only have one, that's the one I want.
01:51:53.560
It's got to be there. I sent you the picture of me sitting in that one.
01:51:57.980
That would have to be number one, but then there's at least 10 that I could pick from Be Happy,
01:52:01.760
but I would probably say, and one of them is one that I have a lot of experience with,
01:52:05.640
which is the Ford GT. I just think that's one. Gen 1.
01:52:07.620
Gen 1, one of the all-time greats. I would probably pick stuff that's manual and somewhat analog.
01:52:13.040
I'd probably have to say Carrera GT, Porsche Carrera GT with an NA V10. They're unobtainium
01:52:18.600
now, but they were reasonable of just a few years ago and they're just, there's plenty of faster
01:52:22.960
cars. A Carrera GT today is going for about 1.7, 1.8. 10 years ago, it was half that.
01:52:29.600
Yep. And what's an F40 going for today? It's got to be three.
01:52:32.760
I think at least. Yeah. I mean, six, seven years ago, it was half that.
01:52:37.980
Do you think this is a bubble or do you think these things are not coming down in value?
01:52:42.020
They're never making any more of those. Limited supply demand is never going to wane for those
01:52:46.300
at least. I think when you look at other collector cars, like some of the pre-war stuff, it's going
01:52:51.100
down because the target market is all unfortunately dying off. Those people aren't around and you
01:52:55.120
appreciate that. And that may happen at some point, I suppose, there's going to be a point
01:52:58.360
where nobody cares about this. We'll probably be long gone by then.
01:53:03.680
And there's so few of them. That's in a completely different league than the other cars, but even
01:53:07.080
like something that Ford GT, they made 4,000 of them. It's not that rare.
01:53:12.060
A lot of them are gone thanks to, yeah, lack of traction control. But still, I don't think
01:53:16.580
they'll ever go down just because that era, I think the Gen 2, the current Ford GT, which is a
01:53:21.340
twin-turbo automatic car, will ultimately be eclipsed in value by the old one, even though right now
01:53:25.640
there's still more. They're almost double or triple, but I think it's going to go the other way.
01:53:32.280
We talked about that a little bit. It's right up there. The only downside to the 959
01:53:36.320
is that it was so ahead of its time. That essentially is what a modern Porsche is now.
01:53:42.740
So yeah, it's super cool. You've got the 80s campiness, the looks, but it's basically like
01:53:47.140
driving a 993 turbo for the most part. It doesn't have that NA V8 or V10 sound. It's a turbocharged
01:53:53.540
flat six, like everything was after it. At that time, there was nothing like it.
01:54:02.440
So modern. Sequential turbos and even water-cooled heads. Those were all air-cooled Porsches back
01:54:08.520
then. They managed to water-cool the heads. And now Canepa does a really cool version,
01:54:12.920
a Restomod version, but those never came to the US. I think you know about that, right? It was
01:54:19.760
I don't know all the details. I should have read it, but essentially he was able to get the
01:54:23.880
gray market to passage for these cars for some loophole. I don't know the details of it. And only after
01:54:29.200
that, were they able to import them into the US? Of course, now that they're older, you can get
01:54:33.260
anything under a 25-year-old. I like the oddball stuff like that. That's just unavailable. The
01:54:38.260
959, I would still put a click below the Carrera GT just because of that naturally aspirated F1
01:54:43.340
drive V10 that just sings and the 959's motor doesn't have that level of character.
01:54:48.900
I'll tell you what's interesting about the Carrera GT, which by the way, would be on my list of three
01:54:52.900
as well. Most people listening to us now, if they're not car nerds, wouldn't spot a Carrera
01:55:01.940
Yeah. That's like a bigger Boxster, right? It's just like-
01:55:04.420
They're like, what is, is that a Porsche? What is that car? Like that doesn't even look,
01:55:07.600
like it doesn't stand out at all. Whereas if you saw a McLaren F1, you don't need to know
01:55:12.620
anything about a car to know you saw something special.
01:55:17.040
And I think the same is too with the GT. The GT is absolute head turner no matter what.
01:55:22.260
And the interesting thing there is it's really based on a 60s design. It was a tribute,
01:55:26.200
but Camillo Pardo, who was the designer for Ford, who basically reinterpreted it for the 21st century,
01:55:32.800
kept that original character, but made it aero-friendly and was able to use all these
01:55:37.140
hard points from the old car, but make it modern and basically upsized the car. It's like 110%
01:55:42.640
size of the original that you could actually fit two people in because the original GT40s were tiny.
01:55:47.380
And they apparently generated tremendous front-end lift in Le Mans. And the modern one,
01:55:52.700
I've actually run at the Texas Mile on an airstrip over 200 miles an hour. It's dead straight.
01:55:57.280
They did everything right without resorting to the modern cars with all the big wings and all
01:56:05.820
Okay. Now of the modern cars, anything that you really, really fancy, let's define that first
01:56:13.460
wave of hypercars in the 2015. So when the LaFerrari, the P1, and the 918 came out, which is
01:56:27.880
So from that era forward, what do you fancy the most?
01:56:32.940
Those cars, again, at that time, I liked them more than I do now, just because, again,
01:56:37.280
the hybrid technology is leaving those kind of, they're a little outdated now. I think out of
01:56:41.200
those three, I was personally, maybe I'm sounding like a Porsche fanboy, but the 918 was just stunning.
01:56:47.020
Part of it was just the design, forget about the performance. And it had an, again, NA V8,
01:56:50.660
high revving, bespoke to that car, not in any other platform. And the electric component was just the
01:56:56.520
gee whiz thing of the moment, which of course made it ungodly fast. But that NA V8 and the way the
01:57:03.260
Well, that's why, by the way, I've got a friend who has all in silver, 959 Carrera GT 918.
01:57:14.240
That's like having, you know, F40, F50, Enzo, LaFerrari, same sort of thing. I mean, all of those
01:57:20.320
cars were amazing, but since then, the interesting thing about that era a decade ago was that was
01:57:24.600
probably the inflection point after which performance doesn't matter anymore. Who cares?
01:57:32.020
Right. And not only that, you can buy a used EV. You can buy a Tesla Plaid that'll do 60 in
01:57:36.760
two seconds flat, 50 grand that'll smoke everything.
01:57:39.060
Tell everybody about the time you took your Tesla Plaid to Koda. How long did it take you to smoke
01:57:50.660
Make sure people understand this because they don't know. So that means you came out of
01:57:54.600
pit lane, right? So you're going up to turn one.
01:57:56.800
I did an outlap. So I did an outlap. But the first, coming down.
01:58:03.540
Going to turn one. And my buddy was in an SF90, which is a thousand horsepower Ferrari hybrid,
01:58:08.580
which is basically the fastest Ferrari you could ever buy. I was catching up with him in 20 and
01:58:13.720
coming down the front straight, I caught an SF90 in my daily driver, but I nearly rear-ended him
01:58:19.540
because the car was able to stop just barely for turn one, but the brake fluid boiled at
01:58:24.780
that point. The car was not designed to do that, unfortunately. And what's interesting
01:58:29.280
thing is you would say, okay, it's an electric car. It's heavy, blah, blah, blah. Other electric
01:58:32.560
cars don't do that. The Lucid, the Taycan, they actually have really good brakes. But at the time,
01:58:37.940
I didn't realize this because they had been advertised as being track ready or at least
01:58:41.240
able to run a, like we're talking about how it ran so good at the Nürburgring. But the factory
01:58:44.700
brake fluid is DOT3. I find out after the fact, which is low boiling point, just boiled it.
01:58:49.480
The car is designed for efficiency, low drag. By the way, I didn't even use DOT3 in my simulator.
01:58:58.280
So a 5,000 pound machine stopping from a hundred and I probably did 160 on the front straight.
01:59:04.900
Yeah. Well, that's about, I think it was limited actually that time. I didn't have a track.
01:59:08.060
The amount of BTUs that you're trying to shed off of those brakes, just forget about it. So
01:59:13.600
The brakes are fine if you put better fluid in?
01:59:17.760
But if you want to track a plaid, you're going to need new brakes.
01:59:21.420
I ended up having a full Willwood setup put on the car. So all new rotors, custom ducting,
01:59:26.240
Mike Dussault, Dussault Designs. Actually, he bought a plaid for himself. He's the guy that built
01:59:30.120
the Z06 I'm driving now. But he ducted into the front brakes, basically custom brake ducts. That car
01:59:35.740
is sealed. The whole front end is sealed. It's not meant for that. It's meant to just be low drag.
01:59:40.960
Nothing. Nothing at all. So he actually made custom ducting. And after that,
01:59:44.900
the car was unbelievable because you could actually late brake and do really well.
01:59:48.880
So what lap time can you do in a tripped plaid now?
01:59:51.580
Here's the problem. You can only get one solid lap before it starts pulling power due to heat
01:59:55.760
to the battery. But my best was a 224. And so that's at a 5,000 pound car. That's no weight
02:00:01.040
taken out. Just a stock car. Didn't do any mods to it other than just the brakes. But you do one lap,
02:00:05.820
just to re-answer your previous question. I don't know how much time we have,
02:00:08.500
but I'll just keep it brief. That one stop turn one, brake's gone. Thank God I have regen. So I
02:00:14.500
just literally nursed it. But I couldn't turn off. So I go through the S's and I'm just 30 miles an
02:00:19.520
hour, whatever I got down through. The regen is enough to keep the car from completely just going
02:00:23.200
off the tracks. 30, 40, 50. So coming through 9, 10, coming into 11. Again, I'm not on the throttle
02:00:27.920
at all. I'm just maybe going 40 miles an hour. But the regen is coming down the hill towards 11.
02:00:33.000
11. The regen has kept me from gaining any more speed. My right foot is on the floor. The fluid
02:00:38.160
is boiled. So I had to go wide in 11 into the gravel, completely around. And then, you know,
02:00:43.300
that's when I found out about all that. And the McLaren Senna both taught me where all those orange
02:00:47.520
squares are spray painted on the arm coat where you can have the emergency offs. So I literally went
02:00:51.780
through the gravel, came within inches of the arm coat 11, and then just hobbled in. But then after
02:00:57.200
that, the next time out, we put Castrol brake fluid in it and changed the pads. Then it was
02:01:03.600
good for maybe a lap. So then ultimately, that still wasn't good enough. So we did the big brakes.
02:01:07.920
Now, I see guys out there with Teslas. They're clearly not pushing as hard as you.
02:01:11.540
Or they're mostly Model 3s. The Model 3 is 800 pounds lighter. It's not as fast,
02:01:16.340
but it's a way better track car. So I've got dozens of laps in Model 3s. They do fine because
02:01:20.360
they're not making 1,000 horsepower and they don't weigh 5,000 pounds. They still will boil their brakes.
02:01:25.020
But if you just do pads and fluid, that's actually a very desirable, especially if it's a little bit
02:01:29.620
damp outside, not much can keep up with you in a Model 3. And autocrosses, they've won national
02:01:33.980
championships with just coilovers in a 4,000 pound sedan. That's where EVs have gotten.
02:01:38.760
But just to answer the previous question, we did the brakes on the Model S. And then once that was
02:01:43.240
done, the only thing that eliminated the brakes as the weak link, but the battery, the cooling is still
02:01:48.100
not there. So you've got guys spending tons of money. I actually was looking at doing a really
02:01:51.860
heavily modified aero Tesla Model 3, like Randy Pope's drives. It'll only do a lap at Coda.
02:01:57.700
It's such a high speed and high braking, but you can hot pit and go right back out and you can keep
02:02:02.100
hot pitting, but you'll never get a full lap time, but it'll do just fine if you do that.
02:02:06.460
But the next gen cars, the Porsche Taycan, even the Lucid Sapphire now, those cars, they're just as
02:02:11.600
heavy, just as powerful, and they can do it. Have you taken the Taycan Turbo S out?
02:02:20.040
At the time I was on stock tires and everything, probably a 230-ish, right around there.
02:02:25.720
I think I probably sent you that video. At John Hennessey's track, I had the Taycan,
02:02:29.760
the Lucid, and the Plaid all lined up on the drag strip. I'm in a 750 horsepower Porsche that can run
02:02:35.340
tens in the quarter mile, and the Plaid and the Lucid walked away from me like I was on foot.
02:02:47.380
This was the old Lucid. Now, the new Sapphire Lucid has more, has 1,200, but this was 1,100,
02:02:52.600
and it's still a tenth or two behind the 1,000 horsepower Tesla.
02:02:57.300
And they're all all-wheel drive. The traction is a non-issue.
02:03:00.560
It's literally just power to weight at that point.
02:03:03.080
So I didn't realize that. So the Taycan Turbo S was only 750.
02:03:06.980
When you stand on a Turbo S, if there's a Plaid next to you, he will leave you like you're not moving.
02:03:11.160
That's like the Audi. It's a super fast car in the real world, but that's why horsepower doesn't matter
02:03:15.060
anymore. But that was more horsepower limited. The Taycan would happily do... And actually,
02:03:19.120
I had a Turbo before the Turbo S, which had steel brakes. Turbo S had ceramics. And even the Turbo
02:03:23.760
would do it on all-season tires. The very first Taycan that came out. This was in the early days
02:03:28.300
when Porsche was... VW was having to respond to Dieselgate. You remember Dieselgate, that whole
02:03:32.820
deal. So they had to build these electric cars, and they had to go to states that were CARB,
02:03:38.280
basically the California Air Research Board, emissions compliant because of all the diesel
02:03:42.060
penalties they had. So the first cars didn't come to Texas. They only went to New York.
02:03:45.620
So I got a non-Turbo S, a regular Taycan, one all-season tires out of New York. And on steel
02:03:51.300
brakes, Porsche's Porsche. I mean, it was squealing in the corners of an all-season tire, but it lapped
02:03:56.180
20 minutes. No problem. Brakes were solid. There's just something about the German engineering
02:04:01.240
there. But having said that, the Lucid is now equally good, if not better, despite being a
02:04:06.620
brand new non-legacy company who is, again, not trying to build a track car. But the Lucid Sapphire
02:04:11.580
is faster than a Plaid now. It runs eights in the quarter mile, but it can actually track. And even
02:04:16.200
my old Lucid, which I was expecting to... It can run eights in the quarter mile?
02:04:20.020
Eight nineties. Yeah, it can crack in sub nine now. It's several car lengths ahead of a Plaid,
02:04:24.400
which is beyond bonkers. You have to warn passengers. These cars now, you can't just accelerate
02:04:29.840
and you have to say, hang on, just put your head against the headrest before I concuss you.
02:04:35.960
By the way, we failed. You very, very briefly mentioned it, but my favorite car post the
02:04:41.640
holy trinity of 2014 and 2015 is, of course, the McLaren Senna.
02:04:46.280
How does the Senna stack up for you? And what was your fastest lap time in a Senna?
02:04:49.740
So my best, again, the biggest limitation of the...
02:04:53.060
The non-GT... The Senna GTR can probably... I've seen guys run like, I think, two flats in those
02:04:57.780
things. I know a coach of mine had run a 208, just barely even trying. But the Street Senna
02:05:02.740
on the Trofeo R, just it understeers. It's really just not meant for that, but it'll still... And
02:05:07.340
it got tons of downforce, tons of braking, but it just doesn't have the grip. So I think the best
02:05:10.980
I did was a 215. And again, when you're driving a car, that value...
02:05:14.360
But that's insane for a street car with street tires.
02:05:18.080
But at the same time, I'm sure a pro could do better. I was still thinking, you know,
02:05:21.480
that arm code gets really close to a car of this value. It could be a really bad day.
02:05:27.520
150, even on Trofeo R's. McLaren doesn't want you to put slicks on it. And so I violated all
02:05:32.600
the rules. I ended up putting a set of Pirelli tires off the Ferrari Challenge cars on it.
02:05:36.600
When I first put it, again, slicks need camber. You can't get much camber out of a Street Senna,
02:05:41.640
which to me was the most disappointing thing. Whereas the GTR, you got four degrees.
02:05:45.200
Even without camber, when I first stopped on that backstreet, completely stocked Senna with
02:05:49.280
just slicks on it, at the 150 mark, I almost parked it in the corner. It was incredible.
02:05:54.000
Even with the Trofeo R to stop at 150 in a tire that drove me to Houston and back,
02:05:59.320
the bandwidth of today's tires, that's a whole nother topic. It's incredible what even an
02:06:03.740
all-season Michelin can generate a 1G. 1G is nothing anymore. All my old car and drivers,
02:06:09.300
I have a library of thousands of magazines. 0.8, 0.9 was a huge deal 30 years ago. Now you got
02:06:14.920
minivans that do that. And even all-season shod sports cars that are heavy can do that on a
02:06:20.420
regular tire. The chemistry of these tires these days is unbelievable.
02:06:30.700
And that's not even on a Pirelli. I'm a cheap guy, so I run-
02:06:35.360
AMG GT3, I was running Hankooks, which would at least last me two weekends. And even then,
02:06:39.920
that car was running 2.11s on Hankooks with just me driving it. So the pros are running faster than
02:06:44.760
that. Yeah. I think Senna GTR, not a street car, of course, but just-
02:06:48.880
The problem with the Senna street car is it's too track for the street and it's too street for the
02:06:52.720
track. A 720S, which is mechanically identical without all the downforce, is a beautiful GT car.
02:06:58.600
Drive it cross-country. You can store stuff in it. Super comfortable. And on Hoosiers, not on
02:07:03.560
slicks, but on Hoosiers, and I changed that to steel brakes, that's a 2.16, 2.17 car. It's not that
02:07:13.420
Yes. The McLaren GT4, that one, I'm sure, I think Randy Popes could probably run close to that.
02:07:19.620
Driver to driver, three seconds probably. And that's all in the straights because the GT4 car
02:07:23.720
has half, well, not half the power, but it has, and actually my GT4, I cheated. I tuned it. The
02:07:28.660
570S GT4 was already detuned from the street car, but you can tune the street cars as well. So when I
02:07:34.220
pushed an extra 150 wheel just by tuning it because stock turbos can handle that. So that would go
02:07:39.360
175 on the back straight, whereas a regular GT4 can do 20 miles an hour less than that.
02:07:44.280
But even then, the 720S, actually the 720S and Senna are identical on the back straight.
02:07:53.780
Yeah. In the 720 with the aftermarket steel brakes, pads, and a Hoosier, which is still a
02:07:59.420
DOT tire, you can still brake it a little bit after 200. It's not bad at all for a car that you can
02:08:04.560
go shopping at the outlet malls in because it's got a massive frunk. And the ride compliance,
02:08:09.020
that's the biggest thing about McLaren. So the Senna is more tied down, but they all
02:08:12.960
have that active suspension that doesn't use sway bars or springs. It's all hydraulic. It's
02:08:17.440
all fully active. There's hydraulic lines that diagonally connect the front right to
02:08:21.440
the left rear wheel. So the pressure in those lines combats body roll. So you can have it
02:08:25.360
be a plush highway ride, or you can have it be a stiff track car. The bandwidth is almost
02:08:32.820
Do you think McLaren is somehow underperforming relative to what they should be doing given both
02:08:37.360
their quality as an automotive brand and as a racing brand?
02:08:41.720
Underperforming in terms of sales, is that what you're talking about primarily?
02:08:44.840
They are. Yeah, they truly are. And a big problem is, I think, is the perceived,
02:08:48.740
I mean, actually, it's not just perceived, the actual lack of reliability. I love the cars,
02:08:53.460
but they're always, it's all the jokes about British electronics, they all come to bear.
02:08:57.000
Even the Senna would go into limp mode on between nine and 10. If you floored it,
02:09:00.520
it wasn't just mine. We had Senna Fest going on with 20, I think we had 20 on track at one
02:09:05.180
time. Some guys were just kind of tooling around, so they were fine. But if you were
02:09:08.420
hauling ass between nine and 10, when you get a little bit of suspension droop,
02:09:11.500
you'd go into limp mode. If you're accelerating through that, I would literally-
02:09:15.320
No, no. I'm sure the GTR is fine. I haven't tracked one of those, unfortunately.
02:09:23.040
That was in track mode. I think it happened to me even one time,
02:09:25.720
I forgot to put it in track mode. I think it still did it. It's a G-Force related to
02:09:30.220
suspension droop issue. They just freaked out the computer. And they had McLaren guys on site who
02:09:37.220
They did. I think it made it less frequent, but I think it still happened after the patch.
02:09:43.260
Well, I think it's safe to say nobody's listening to us anymore now anyway, but
02:09:47.100
in case anybody still is, this has been an awesome discussion.
02:09:51.220
I really appreciate the offer to come out. This is a true privilege. Peter,
02:09:54.980
what you have done in this community is unparalleled in terms of, I think I told you when I first met
02:09:59.720
you, I was like, dude, how do I get CME for this stuff? Your lectures are better than almost all,
02:10:03.380
not lectures, but your podcasts are better than almost all the CMEs because you get the right
02:10:08.140
quality people on here, much better than me by far. And the way you phrase the questions and the way
02:10:12.920
you parse everything, it's so understandable for a wide bandwidth. I got my non-medical friends and
02:10:18.440
family all the way to the colleagues. Everybody gets something out of them and that's hard to do.
02:10:23.140
Well, hopefully today we delivered a lot of insight, both to people who are obviously interested in
02:10:27.980
radiation therapy for cancer, which unfortunately is going to be a lot of people.
02:10:31.180
And then of course, this other application around the treatment of inflammatory conditions,
02:10:36.060
which again, inflammation lies at the root of so many other things. And just in case anybody cares
02:10:41.220
about a little drumming in cars, hopefully they got something too.
02:10:44.240
I think we have a whole indication for a whole separate series here that truly is the drive.
02:10:52.560
Thank you for listening to this week's episode of The Drive. Head over to peteratiamd.com forward slash
02:11:00.580
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