#485 — The New Science of Cancer
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1 hour and 21 minutes
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Misogyny
2
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Summary
In this episode, Dr. Siddhartha Mukherjee interviews the Pulitzer Prize-winning author of "The Emperor of All Maladies: A Biography of Cancer" about his updated edition of the classic book. They discuss how our understanding of cancer has changed in the past 15 years, and how we should think about it as a disease.
Transcript
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You have an updated version of your Pulitzer Prize winning book, The Emperor of All Maladies,
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A Biography of Cancer, which came out 15 years ago, but you've updated it.
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And I think there are four new chapters in the new paperback.
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I want to spend some time on how our thinking about cancer has changed in the interim.
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And I think we'll break this into three chapters, prevention, detection, and treatment slash
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But also you have an AI startup, which I want to talk about because the utility of AI here in any one of these stages is obviously something that people are hoping for.
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And I'm glad to see you're trying to push that forward.
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But let's start with just kind of the basic conceptual framework and maybe how that's changed in the intervening years.
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I mean, this is a, are there, is it a hundred different forms of disease?
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I mean, when we get a cure for this thing, is it going to be one cure or are there going
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Well, I'm almost certain that there'll be hundreds, but there'll be common themes running
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So one thing, one question that I, you know, try to answer very often is exactly the question
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you asked, which is, you know, is it a hundred different things?
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If it's many diseases, why do we call them cancer in the first place?
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Why shouldn't we just separate all of them out?
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And the answer is somewhere in the middle. It's every form of cancer. In fact, every individual
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form of cancer, every individual specimen of cancer is its own disease in the genetic sense.
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So in the sense that, you know, a one woman who walks into your clinic with, let's say,
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breast cancer has a particular spectrum of mutations. Mutations are changes in DNA
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that drive the cancer cell's growth. The second woman might come into your clinic with breast
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cancer looks the same under a microscope. It's called breast cancer, but her spectrum of
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mutations, you know, maybe she has 100, maybe she has 20, her spectrum of mutations is slightly
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different. So why do we call them all of them cancer? Well, first of all, there are some broad
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physiological commonalities. So the broad physiological commonality is that in all cases,
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the first woman, the second woman, the third woman, all with breast cancer, in all three cases,
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the problem is that the cells don't know how to stop dividing. And in a few cases,
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they don't know how to stop living or essentially they don't know how to die. But let's say that
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most of the most part, they don't know how to stop dividing. And driven by that malignant growth,
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these cells, these cancer cells have started co-opting, hijacking, you might call it,
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normal pathways that normal cells use to survive. So just like normal cells use nutrients to
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survive. Cancer cells also need nutrients to survive. You could say they need kind of a special
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kind of nutrient to survive, special kinds of nutrients to survive, special pathways that
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they've hijacked from normal cells. Just like normal cells in the body move around and go to
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other places, cancer cells also acquire the property to move around. So there are deep
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commonalities that run between all these diseases called cancer. And yet it's also true that each
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individual specimen of cancer in its own cancer. Is there one conceptual bottleneck here that most
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troubles you in our making progress? I mean, is there one question that if we had the answer to
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it, you think it would unlock the greatest promise here for treatment or prevention or
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detection or all of it? Well, I think we should really speak about prevention, detection, and
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treatment differently. Let's start with treatment. I mean, the big unlock for treatment is always
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going to be, can we find something in the cancer cell that's different from the normal cell? That's
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always been the problem. Cancer cells are very close cousins, if you will, to normal cells. And
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that's obvious because they're derived from normal cells. So the big conceptual unlock here
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is, can we find one pathway, two pathways, five pathways, 10 pathways that are different enough
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Ultimately, all the signals are going to the same place.
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is to find the difference, the unlock, as it was it were,
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is doing and what the normal cell is able to do and is doing. If you can find that unlock
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across not one, but multiple specimens of cancer, we'll have different treatments.
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There may be some common ones, there may be some different ones, but that's the big unlock there.
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Okay. Well, let's go back to prevention because it seems like the right thing to put first here.
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So we know that lifestyle and other variables can affect one's cancer risk significantly. I mean,
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there's the environment, there's lifestyle, there's vaccines, right? We have vaccines for
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certain preventable cancers. Why is, in your view, is prevention kind of an afterthought? I mean,
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is this a science problem or an incentives problem? And why do we think about prevention last?
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Well, we shouldn't be thinking about prevention last. And to be totally honest,
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this has been known for a while that it should not be an afterthought.
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The problem is that prevention science is probably the most difficult science,
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because you're trying to do something and not have it happen.
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You know, scientists are used to, heuristically,
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and then stopping them from happening or starting them from happening.
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In prevention, what you're trying to do is trying to create something
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And so prevention trials, to give you one example,
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you're essentially giving normal people something or exposing normal people to something or changing
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normal people's behavior and making sure that they don't get cancer as a result of that change.
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And you can imagine, given us, if the incidence of cancer is relatively small, let's say it's,
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you know, a hundred in every hundred thousand people, you can imagine that that trial stretches
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on for 10 years or five years until you really understand how to prevent cancer. Now, you can
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take shortcuts. You can take people with high risk disease or high risk for cancer, high genetic risk
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for cancer, and then you can have a shortcut to getting a better study. But that's always been
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one of the big questions in science. The other problem is that there is really no surrogate,
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and I'll tell you what a surrogate is, but there's really no surrogate for the development of future
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cancer. I'll contrast it with heart disease. The huge difference in heart disease is that in
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cardiovascular disease and when you have heart attacks, myocardial infarctions, we discovered
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that there were biomarkers for myocardial infarctions. So in other words, if you had
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high cholesterol of the wrong kind, you would have a higher chance of getting a heart attack
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in the future. So now you have a biological marker called a biomarker or a surrogate in which you
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say, well, okay, instead of waiting for the heart attack to happen, if I can lower that bad
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cholesterol, that's a good trial. I can prevent a heart attack from happening, and the end point
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of the trial is I'm going to lower the cholesterol. Another example, hypertension. We know that high
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blood pressure is related to having heart attacks in the future. I can say, okay, well, lowering
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blood pressure, which I can measure, is going to prevent heart attacks in the future. Unfortunately,
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there isn't something like that. There isn't a hypertension or a high cholesterol for cancer.
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You have to actually, unfortunately, for most cancers, wait for the cancer to happen.
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And that has been a very difficult bar because, obviously, these clinical trials, any methods,
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But there are basically two very broad ways that people try to figure out how to prevent
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cancer or what causes cancer and how to take them away from our environment.
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So one way is to look for, since cancer is a disease of mutations, one way is to look
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after a fellow named Bruce Ames who invented it.
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it'll cause, it'll catch x-rays as a carcinogen,
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and you ask if animals get cancer. Now, obviously you can realize that there are some things that
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you can't make a mouse smoke, for instance. So you have to find a way to paint the mouse with
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tar to get the mouse to see if that causes cancer. And the third way is a large epidemiological
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study. So in other words, you follow a large population of people and you could ask the
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question, is there a higher rate of cancer among those people? For instance, is a higher rate of
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of lung cancer and mesothelioma in people who work in asbestos factories. So you say, okay,
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asbestos is a carcinogen. How can I prevent those mesotheliomas? I'm going to take asbestos out of
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the environment. If the AIMS test, the one, the first I referred to, suggests that x-rays cause
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cancer, how can I prevent cancer? I'm going to try to reduce your exposure to mutation-causing
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x-rays. You have a substance that causes cancer in animals. How do I reduce cancer? How do I
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prevent cancer? I'm going to take that away from exposure to humans. So those are the three broad
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ways by which we can, and I've left out a couple, but those are the three very broad ways that one
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can understand how to prevent cancer. But whatever happened to the cell phones
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cause cancer story that hit the news about 20 years ago? This actually predates the smartphone.
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I remember we all had our flip phones, and we were all terrified about stories of lateralized
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And then I think it's been decades since I've heard a story along those lines.
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Do we all just have more brain tumors and just we're so attached to our smartphones
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So if you look at the incidence or if you look at mortality from glioblastomas or brain
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tumors in the United States, it has remained flat over multiple decades. One can have lots
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of arguments about some people who have fancy mechanisms by which they claim that cell phone
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and cell phone radiation causes cancer. Just to be very clear, the radiation that is coming out
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of your cell phone is completely different. Physics-wise, it's completely different from
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the radiation that you get from x-rays, for instance. They're both called radiation because
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ultimately they're forms of energy transferred through radiance, but they are completely
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different. They are completely different in energy. They're completely different in their
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properties. And so mechanistically did not make sense. And the ultimate proof of the pudding is
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that the use of cell phone has skyrocketed in the world and in the United States and the mortality
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or are we nowhere near even thinking about that?
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and let's air out some, I would say, some laundry
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whether dirty or not, some laundry from the prevention world. So this fact often surprises
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people. The surprising thing is until recently, and I'll talk about what recently means,
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we really have not found a chemical carcinogen with large human impact, a preventable chemical
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carcinogen with large enough human impact to make a real difference in cancer prevention
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since the 1960s. So just take a minute to swallow that fact. Billions of dollars have been poured
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into prevention research. And certainly we found chemicals that cause cancer that can be removed
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from certain environments. I'll give you a couple of examples. I'll give you one already, asbestos.
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I'll give you another example, formaldehyde. But usually these are in niche populations,
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and they're in populations where asbestos workers, woodworkers exposed to formaldehyde.
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So there really hasn't been an absolute revolution in which I can say, here is a chemical widely present that you are exposed to and I'm exposed to, which increases the risk of cancer substantially.
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That is changing. I'll tell you about the change in a second. But before I do that, you could ask the question, well, why not? Why haven't we found them?
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Well, the answers could be many. Number one is that it could be that there aren't so many.
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That would be a difficult answer for us to swallow because we all want to prevent cancer.
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Number two, we don't have the right methods to look for them.
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You know, the tests I told you about, the Ames test and the mouse animal tests and the
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epidemiological studies just aren't strong enough to find these kinds of carcinogens,
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or maybe we need a different kind of test to trap these kinds of carcinogens.
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And then, you know, it's also possible that it's a death by a thousand cuts problem.
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So they do exist, but they just sort of fly under the radar of all these tests.
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And it's the combination of them, somehow or the other, that's causing cancer.
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And finally, the one thing I said, just to remember, I made an important caveat.
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I said, chemically preventable carcinogens, we have discovered since that time, since
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A great example would be human papillomavirus, and there's a great vaccine against it.
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But just to remind you of what I said, since the 1960s or 70s, we have not found a preventable
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chemical carcinogen of significant magnitude to make a difference in human cancer mortality.
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So that would be a sad statement if I were to continue that line of thought, but that's
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And that's changing because we've discovered recently, we've begun to discover a new class
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And this class of chemical carcinogens will not be caught by the Ames test.
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This class of chemical carcinogens is unlikely to be caught by animal tests because the reason
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What this class of carcinogens is, is it changes, if you think of cancer as a seed and its environment
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It changes the soil around the cancer and thereby enables the cancer cells that were
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previously dormant or asleep, it encourages them to start growing. And there's been a recent spate
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of studies, most importantly, a study around particulate air pollution. So very small particles
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of air pollution, which are now coming out to be a preventable human carcinogen because you can
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remove the air pollution. And the way that particulate air pollution seems to work is not
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the way that we think standard carcinogens work. So it does not cause mutations in cancer cells
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and thereby unleash cancer by causing mutations like, I told you before, like x-rays or potentially
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formaldehyde, but it rather changes the soil around the cancer cell and thereby unleashes
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the growth of a previously dormant cancer cell and makes the tumor grow. And particularly air
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pollution is an example of this, there's a strong suspicion that asbestos is an example of this.
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For a long time, we didn't know why asbestos, even though it was a very potent carcinogen,
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we didn't know why asbestos caused cancer. We think that this is potentially how asbestos
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causes cancer. So that leaves the question of what exactly is happening? What is it doing?
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And the answer is that these new substances, in my book, I call them inflammogens,
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These new substances cause a particular form of inflammation, not any kind of inflammation,
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but a very particular form of chronic inflammation.
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And cancer cells love to breed and grow in the soil of that chronic inflammation.
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And that leads to two very important consequences.
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Number one is that if we could find a measure of chronic inflammation, this particular kind
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of chronic inflammation, we may be getting closer and closer to finding that magic thing that I
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talked about before, which is a biomarker for future cancer. So that's one thing. And secondly,
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of course, we can devise tests. Just like we devised a test for capturing x-rays and other
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things that cause mutations, so-called mutagens, we could devise a test for inflammogens. And these
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inflamogens are potentially things that we could remove from our environment, remove from our
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bodies, remove from our body, physiological states in our bodies, and thereby reduce the risk of
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cancer. So it'd be a new way of thinking about prevention. And this would actually be a very
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revolutionary way of thinking about prevention. What about anti-inflammatory drugs that, I mean,
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whether you can control the variables in the environment or not, what about just bringing down
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So it's, again, you said the word generally, and it's the generally part that doesn't work.
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This is the very specific kind of inflammation. It's mediated by a particular kind of cell in
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the body called a macrophage. A macrophage is named because it's a, a macrophage really means
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big eater. It's a cell that goes around the body sort of scavenging all sorts of things like dust
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particles, I should say, particles of pollution. Macrophages, you know, often have, in asbestos
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workers, you can see them sort of trying to eat the asbestos, the tiny, tiny needles of asbestos.
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So it's a very particular kind of inflammation. And yes, if we could find a way to find people
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who had exposure to that kind of inflammation or had high levels of that kind of inflammation
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and potentially prevent that inflammation in those people, yes, there would be a chemoprevention.
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There is a very good chemoprevention for a very particular kind of cancer that works
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very well, which is estrogen receptor-driven breast cancer.
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So we know that breast cancer, we've known this for a long time, breast cancer is some
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kinds of breast cancer, not all kinds of breast cancer, but so-called ER positive.
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So estrogen receptor-positive breast cancer thrives on estrogen.
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Estrogen is a natural hormone made by the body,
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but you can give drugs that modulate or modify the cancer cell's response to estrogen,
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and those are very good chemoprevention for patients who are at high risk for breast cancer.
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We don't give them to everyone because they have significant side effects.
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We don't give it to everyone, but for patients who are very high risk for breast cancer,
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There have been several studies now that show that if you give them these anti-estrogenic
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pills, they have to deal with many side effects.
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But if you give them these anti-estrogenic pills, you can actually have chemo prevention
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So here's a final question on the prevention topic.
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How should people think about their risk when they have some information about it?
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It might be family history or a polygenic score or some other information that they
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have, which makes them feel like, you know, I think in this case, accurately, that they have
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more than a normal risk for a certain kind of cancer. How do you recommend people process that
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information personally without, you know, falling into fatalism or despair or some form of panic?
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I mean, you as an oncologist, how do you walk people through that?
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So first of all, I think, you know, I've written a lot about this. I think, you know,
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there's a whole phenomenon. It's a chilling Kafkaesque word called previvor, which has
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entered the vocabulary of cancer. And a previvor is sort of derived from the word survivor,
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but a previvor is a person who thinks they're going to get cancer, but they don't have it yet.
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They're driven by the anxiety and the fear that they're going to get cancer, but they've not had
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it yet. They're not a survivor of a cancer. They're a previvor of a cancer. And the number
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of previvors is increasing dramatically in the world because all sorts of tests surround all
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sorts of genetic tests and other tests surround and sowing a lot of fear in people's eyes and
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brains. The way I advise people to think about this is to really have a, even if it's a grayscale
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quantification, a grayscale understanding of their risk. And by grayscale, I mean there are some
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people where their genetics and their family history is very strong. So a great example would
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be patients with the BRCA1 gene or the BRCA2 gene. Those patients have, or those people,
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before they become patients, they have a very high risk of getting, for instance, breast cancer.
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It's especially higher if in the context of when they have a very strong positive family history
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of breast cancer. So those patients, I advise going to a genetic counselor and seeing the
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genetic counselor and seeing if they should enroll in one of many trials that are now available
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to screen them more effectively, potentially to put them on, you talk a little bit about
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chemoprevention, or potentially to put them on a trial for a novel chemoprevention for those
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cancers. So that's the advice I give those people. Then there's a second, again, moving along the
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grayscale, there's a second category of person who has what you call a polygenic risk score.
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Now, polygenic risk score, let's unpack that word.
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So polygenic risk score is a person who doesn't have one of these genes like BRCA1 or P53
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mutations or one of these inherited mutations in genes where their risk of getting cancer
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is ginormous because the genes are mutated, but they've inherited a mutated gene from
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Polygenic risk scores, you can think of them as, if you think of the BRCA1 gene as a
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something that shoves you towards getting cancer. I apologize using that analogy or metaphor.
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These are genes that nudge you little bit by little bit towards higher and higher cancer risk.
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They're quantifiable. So you can quantify them. If you sequence a genome, you can quantify them.
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And patients with very high polygenic risk score, for instance, for breast or ovarian cancer,
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I usually assuage them. I generally tell them that these polygenic risk scores
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are still early in their study. And I tell them to see a genetic counselor, but not to be as
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worried as patients with, for instance, the BRCA1 or the P53 mutation. And then there are
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patients who have no family history, no polygenic risk score, no real risk upfront of getting
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cancer, but they are still worried. And I say to them, well, it's a risk that you have to take
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with aging. Cancer is a disease of aging. We all are at risk. And if you feel that you have
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a particular exposure in your childhood. For instance, your father was an asbestos worker.
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Those are the patients that I send for deeper testing, genetic counseling, etc. But in those
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patients, we're really a little bit stuck in some ways. The last one, the last category I've left
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always separate. I always leave it separate because it's a very unique category. And that is
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if you're infected with a virus that causes cancer. And a great example of that is human
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papillomavirus. So if you have a human papillomavirus infection, you are indeed at a higher
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risk to get cervical cancer, depending on the strain of human papillomavirus. Not all strains
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cause this, but some strains, we call them the teen strains, increase the risk of human papillomavirus.
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If you have that strain, if you're infected with human papillomavirus, then you should certainly
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be seeing a gynecologist who should follow you to make sure that your risk of cervical cancer
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is decreased and they may have to do a biopsy or even potentially invasive surgery to decrease that
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risk. Which brings me to a side point, which is that there are incredibly effective vaccines
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against human papillomavirus. And please don't believe the nonsense that's been perpetrated
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about vaccines against cancer. These are extremely effective. I believe that both men and women,
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young men and young women, young boys and young girls should get these vaccines.
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And a massive study in Sweden showed that if, and this was a randomized controlled study,
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the hardest, most rigorous kind of study that exists, a massive study in Sweden showed that
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if you gave the appropriate age, the appropriate number of vaccines for human papillomavirus,
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the dangerous strains, the risk of getting cervical cancer in adulthood goes to zero,
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zero so so we are committing a terrible i would say you know it's a terrible tragedy that across
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the the global world there are still women dying of cervical cancer caused by papillomavirus this
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is a completely preventable cancer well when you qualify it saying young men and young women is
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that just a matter of uh kind of population level um triaging of resources or you actually think
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the utility of being vaccinated goes way down as people age. Well, this is a very particular
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situation. So human papillomavirus is a sexually transmitted disease. And obviously, young men and
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young women are the most at risk because they are the most likely to have an infected partner
00:26:50.480
or have multiple partners, one of whom carries an infection. So it's just a consequence of human
00:26:55.520
behavior. It's a behavioral risk. But if someone is 40 years old and they don't show any titers for
00:27:01.260
HPV and they're, you know, single and sexually active, is there any reason why you wouldn't
00:27:07.360
recommend that they get vaccinated for it? So there's no reason that they wouldn't get
00:27:11.860
vaccinated for it, except that those populations have not been studied because the studies have
00:27:17.220
been done in young people. But biologically or physiologically, there's no fundamental reason
00:27:23.320
that if they were negative for human papillomavirus to start with, that they would not
00:27:28.100
respond to the vaccine. There's no biological reason to think that all of a sudden their
00:27:31.640
immune system will flicker off and not be able to drive a response against human papillomavirus.
00:27:36.000
Right. Well, we won't ask RFK Jr. his advice on this topic. We might get to our political
00:27:43.200
moment eventually. So let's talk about detection. So there's been a lot of excitement around
00:27:49.340
so-called liquid biopsies, you know, blood tests that detect so-called cell-free DNA that I think
00:27:55.540
they're up to, you know, 50-some-odd cancers, specific cancers they claim to detect. I have a
00:28:01.000
little bit of experience with this. I have taken a couple of these tests, one of which was positive.
00:28:07.380
It turned out to be a false positive, but I, you know, then did subsequent scanning and, you know,
00:28:12.820
spent a week imagining that I had a greater than 50% chance of having, you know, one or two or
00:28:18.340
three different cancers. So I've experienced some of the downside of this. Give me your thoughts
00:28:24.080
on around the risks of moving too fast on this and where you think it is headed and what will be
00:28:30.060
the stable point if it's achieved where we're not continually running the risk of over-treatment
00:28:38.120
and, you know, kind of painful encounters with misinformation. Well, so people think that your
00:28:44.800
case is, your anecdote is atypical, but in fact, it is the most typical. So the most typical
00:28:51.260
anecdote, which is not being publicized, there are a thousand companies that do work on cell-free
00:28:57.000
DNA. And I'll try to distinguish the ones that are doing actually good work, but your case is
00:29:01.760
actually typical. But to understand why it's typical, you need to understand something about
00:29:07.020
nothing. It has nothing to do with cancer, but it has to do with mathematics. And this is pure
00:29:11.140
mathematics. I wrote a piece in the New Yorker. I got all sorts of hate mail for it. But the
00:29:15.540
problem is that you can't argue against pure math. Math is math. And the math is very simple
00:29:21.280
in this case. And the math, I won't give you the formula, but it's based on the observation
00:29:26.460
of a very important man whose work has inspired computer science and pure mathematics and
00:29:34.760
statistics, and that's Thomas Bayes. So Thomas Bayes lived in Greater England, and he made a
00:29:42.800
very simple statement, which he then made into a mathematical formula. And the simple statement is
00:29:48.240
that what he called the posterior, what was later called the posterior probability that you have
00:29:55.980
cancer. In other words, whether you do have cancer or not, whether in a population, if I'm measuring,
00:30:01.580
if I have a test that's measuring whether someone has cancer or not, depends on the prior probability
00:30:08.680
that there's cancer or not. So how do we explain this? Here's a simple analogy.
00:30:13.420
Let's say you make a genius detector, a needle detector, and you're looking for a needle in a
00:30:18.340
haystack. So you have a massive haystack and there's one needle buried in it. And you have
00:30:23.320
a good detector. It's 90% sensitive and 90% specific. In other words, it means that 90%
00:30:30.800
of the time when it says it's got something, it actually turns out to be a needle. You go into
00:30:37.880
the haystack and you start, the detector beeps, and you find that it's actually not a needle,
00:30:43.400
but actually a piece of hay. You go into the haystack again, it beeps, and it's another
00:30:47.780
piece of hay. And the third time, and the fourth time, and the fifth time, and that's because
00:30:51.500
there's only one needle in a massive haystack. The prior probability, this haystack was stacked,
00:30:57.320
as it were, with stacked poorly against you. And no matter how good your detector is,
00:31:03.740
no matter how smart your instrument is, it's always going to detect more hay than needles.
00:31:09.480
Does that make sense? It should be very obvious. Yeah, yeah. I recommend that people take,
00:31:14.060
we can't do it here, but take a little time to understand Bayes' theorem and Bayesian reasoning.
00:31:19.340
But I mean, the background frequency of the thing you're trying to detect obviously changes the
00:31:26.600
likelihood that you produced a, however valid the test, you've produced a real positive as opposed
00:31:34.180
to a false positive. So just to finish up, yeah, go ahead. Yeah, but in this case, like we have a
00:31:39.320
company that is advertising its false positive rate, you know, its type one error rate of one
00:31:44.920
in 200, right? So they put the, you know, their Bayesian reasoning, you know, given the incidence
00:31:50.120
of cancer and the cancers they're trying to detect, they're advertising their false positive
00:31:56.220
rate as, you know, half of a percent, and therefore you as a consumer get a positive
00:32:01.980
finding and you think, well, okay, there's a 1 in 200 chance this is wrong, but I don't
00:32:09.620
find that very consoling because the report is telling me I now have a 57% chance of having,
00:32:14.800
you know, either, I think in my case it was, you know, kidney and bladder cancer or prostate
00:32:18.860
cancer or both. And so presumably we're going to get to a place where we're going to find that
00:32:27.140
the error rate is low enough so that, I mean, obviously we have to live with some false positive
00:32:34.000
rate and also there's also the false negative rate, which is real cancers that are undetected.
00:32:38.760
The fundamental mistake that we're making here is the one you just actually,
00:32:42.280
just, you exactly enunciated what the mistake was. The fundamental mistake is that most of
00:32:49.100
these companies are advertising their sensitivity and specificity. So in other words, they're saying
00:32:54.500
our test is really sensitive and it's really specific. What they're not telling you is what
00:32:58.880
Bayes would call the prior probability. The prior probability, the base rate of cancer
00:33:04.680
is low. And until no test, I suppose you can make a test that's a hundred percent
00:33:12.280
specific and 100% sensitive, but that's sort of an impossibility at this point in time.
00:33:17.440
But no test will ever change the prior probability because the prior probability of something is a
00:33:24.000
given. It's how much cancer is there in a population. That's a fixed number. So the
00:33:30.720
answer, I'm going to twist this around and give you a positive answer to the question.
00:33:36.140
If these companies, many of these companies were less greedy and if they were less driven by
00:33:41.340
trying to screen everyone and make money out of everyone and put anxiety into everyone,
00:33:46.700
this is actually the basis of my long piece in The New Yorker, and it's actually in the book as
00:33:50.520
well. If they were less consumed by consumerism, which is to say, I'm going to use this for
00:33:58.400
everybody, then they would identify patients who are truly at a higher risk for cancer. So in other
00:34:04.580
words, they would find populations where the base rate was higher. And sure enough, in those
00:34:10.300
populations, I'm absolutely confident that tests like cell-free DNA will be helpful.
00:34:15.720
So who are these people? Who are these people who have higher base rates of cancer? Well,
00:34:20.640
we talked about some of them already. If you have a mutation that is likely to cause a higher risk
00:34:26.460
of cancer, possibly, I'm not sure about it, but possibly if you have a polygenic risk score,
00:34:31.260
so the NUD genes that I talked about, which increase the risk of cancer, fine, you take
00:34:35.880
those people. You could take people who have had prior cancer before and ask the question,
00:34:40.940
is that cancer relapsing? That's another population where the base rate is higher.
00:34:46.040
And in all those cases, if the trials had been done with patients with all those cases,
00:34:51.060
then the chances of detecting a stage one or stage two cancer, something that actually you
00:34:55.940
can do something about, would have been much higher and is much higher in the small numbers
00:35:00.280
of trials that have done this. So that's the answer. It's a very simple answer. Thomas Bays
00:35:04.720
knew the answer 200 odd years ago. And it's amazing to me that in 2026, we're having a
00:35:11.940
conversation, not you and me, but the global public is having this anxiety-ridden conversation
00:35:16.820
about, oh my God, should I not test or should I test? The answer is, well, what is your prior
00:35:22.040
probability? What do you think? What has moved the needle? Where are you on the grayscale?
00:35:26.660
If you think that you're farther on the grayscale, your father had prostate cancer,
00:35:30.860
your grandfather had prostate cancer, you're worried. Yes, a self-free DNA test might be
00:35:35.780
useful. If you're just someone... But presumably some reduction in the rate of type 1 errors,
00:35:43.380
false positive errors, you could bring it so low that you wouldn't feel that you had to assess
00:35:49.700
your prior probability by being part of some special population of heightened risk. You'd say,
00:35:54.520
I'm a homo sapiens. There's some rate of cancer out there. And if they're giving me a 1 in 500,000
00:36:03.040
false positive rate, that's very different than 1 in 200. And I could do the calculation.
00:36:10.420
Fair enough. But actually, if you do the calculations, again, I would encourage people
00:36:15.220
to just... You don't even need to do the calculation yourself. You can go into Google
00:36:19.500
Gemini and ask Google Gemini to do the calculation for you, but you don't need to do the calculation.
00:36:25.020
But yes, absolutely right. At some point of time when the rate of type one error would be reduced,
00:36:31.660
yes, that test becomes relevant. The problem here is that the ultimate positive predictive value,
00:36:40.300
the number you're really looking for is if the test is positive, what are the chances that I do
00:36:44.700
you have stage one or stage two cancer, right? That is the ultimate, that's the answer you're
00:36:50.000
looking for. So again, to repeat the answer, if the test is positive, what are the chances that
00:36:55.000
you have a stage one or stage two cancer, not stage three, not stage four, but stage one or
00:36:59.560
stage two cancer for which I can actually do something? That number is highly, highly dominated
00:37:06.880
by the prior probability. So even if you increase or decrease the type one error,
00:37:12.740
that number will continue to be dominated by prior probability. And yes, of course,
00:37:16.960
in the envelope of time, in the envelope of things, if you decrease the type 1 error, yes,
00:37:22.400
you're going to start getting a situation where the test is worthwhile doing. For stage 1 and
00:37:27.160
stage 2 cancer, we're far from that yet. Along these lines, obviously different
00:37:31.260
technology, different, maybe every relevant way, but how do you feel about whole body MRI scans as
00:37:38.180
a prevention technology or detection technology. Basically, almost same story, except unfortunately,
00:37:44.740
I feel that the rate of what you call the type one error, or in other words, something is found,
00:37:51.500
but it's not really cancer. That kind of error is even higher. So I don't see that moving in the
00:37:58.440
right direction. I do... But Sid, I think that I completely understand the liability there,
00:38:04.780
but that seems to apply to a first scan. Yes, I was just going to come to that.
00:38:09.960
But if you've had a first scan as your baseline scan, then every subsequent scan is a measure of
00:38:15.660
change against that first scan. So I was just going to come to that. So there's a temporal
00:38:19.100
quality to this, which is what you're talking about. And that we have, to be totally fair,
00:38:25.980
we have not fully tested yet. So right now where we are is we're testing one scan at a time and
00:38:33.960
you know, whether you get a stage one cancer detected or not. It is probably fair that the
00:38:40.260
type one error reduces over the temporal axis over time and potentially reduces to a point
00:38:48.660
of time or to a point or a number where it actually is worthwhile potentially doing more
00:38:54.160
invasive tests like a biopsy or another kind of test. Let me just clarify. I want to make sure
00:39:01.020
everyone understands the distinction we're making here. So with a first scan, the problem with
00:39:04.760
getting your first full-body MRI, let's say, you know, you're a 50-year-old man and you're worried
00:39:10.280
about cancer and someone, you know, your doctor has advertised to you the possibility of getting
00:39:14.420
a full-body MRI. This is, you know, there's no ionizing radiation. It's totally safe. Why not
00:39:20.220
do it? It's $2,000, but it, you know, you get every voxel of your body scanned in an hour
00:39:26.440
looking for tumors. The problem with the first scan is that if you see something, you don't
00:39:32.400
know whether it's been there for 30 years and it's nothing or whether it's a quickly growing
00:39:37.500
cancer. And the prospect of being led on a wild goose chase that entails, you know, biopsies of
00:39:44.840
organs or more invasive scanning, all of that is a clear liability here. And the question I've
00:39:52.500
just asked you, Sid, is yes, but you price all that in, you get your first scan, it's clear.
00:39:57.440
Now your second scan seems to promise some much more valid information wherein anything that has
00:40:03.920
suddenly emerged in your liver or lung or anywhere else suddenly seems like this is new and worth
00:40:10.260
checking out. Well, let me challenge you back with two scenarios which may complicate that
00:40:16.660
answer a little bit more. First of all, let's say your first scan actually does find something.
00:40:23.320
It's a spot. Actually, Dhruv Kullar wrote a nice piece on this in the New Yorker,
00:40:27.040
if anyone's interested in reading further about this. But anyway, I think the company in that
00:40:32.380
case was called Prenovo. There are many out there. Anyway, your first scan, let's say it
00:40:37.420
actually does show something. The question you want to ask yourself is how many people are
00:40:41.060
totally comfortable sitting and waiting for their next scan at, let's say, six months from that time
00:40:47.540
and not doing a biopsy. And if you ask people, I see patients in real time, I see real people in
00:40:53.600
real time, the number, you'll be surprised. No one wants to sit and wait. Wait and see what
00:40:59.380
happens and wait and see it grows. That number is very small. So already you're committing a kind of,
00:41:04.840
you know, you're pushing people down the pathway of invasive tests, biopsies, and so forth. But
00:41:09.600
fair enough some people might say okay you know the first scan has is has shown a spot i want to
00:41:14.680
see if that spot is really growing or not if it's going at what speed and you know if it's cancerous
00:41:19.240
or not fine the second thing i would say about this is is is a point that is often missed but
00:41:26.620
is is is very important so i'm going to try to say it a little slowly but try to make people make
00:41:32.280
sure people understand when you have so let's say we decide that this these tests are a full body
00:41:39.100
scan is a useful test, or even cell-free DNA is a useful test. Let's say we decide that.
00:41:44.000
So then the question becomes, well, how do you judge whether it's really useful or not?
00:41:48.580
And someone's answer, not your answer, but someone's answer is going to be, well,
00:41:52.480
we should just measure survival. How long has someone survived once their scan has detected
00:41:57.680
something positive? But that's the wrong answer because it's a classic pitfall or a bias in
00:42:03.540
statistics called lead time bias. And in other words, what you've done is the person who didn't
00:42:08.160
get scanned, may also have had a cancer, but because they didn't get scanned, we don't know
00:42:12.640
when they get the cancer. Whereas your clock starts ticking the moment you get the scan.
00:42:17.480
So if your clock says that you lived three years after the scan and someone else who didn't get
00:42:22.920
scanned dies at the same moment, you'll think that, oh, you lived three years, that person
00:42:27.520
lived shorter times because their cancer was detected much later, so-called lead time bias.
00:42:33.880
you'll say, oh God, this test is wonderful. But in fact, that's not true. It's just a biased test.
00:42:38.680
So what you need to measure, if you really want to measure, is mortality. And measuring mortality,
00:42:44.900
just again, numbers, pure math, measuring mortality is hard because people die at a
00:42:50.300
certain base rate. And so you have to have a massive number of people in your trial to measure
00:42:54.500
mortality. So those are the two caveats. So if you were to tell me that people are comfortable
00:43:00.260
with having a spot in their bodies, wherever it might be, a lung, a prostate, liver, et cetera,
00:43:06.100
if they're comfortable getting repeat scans without biopsies, and if you tell me that there's a trial
00:43:12.740
that shows that invading on those growing things, whatever they were, actually decreased mortality,
00:43:19.940
I would say yes. But those are very high bars. And you say that research hasn't been done,
00:43:24.780
right? And also there's lots of confounds here. Anyone who's getting a full body MRI at this
00:43:30.160
point is obviously in a very specific population and it'll be hard longitudinally, it'll be hard
00:43:35.320
to separate all of that. I mean, they're doing all kinds of other things. Those studies haven't
00:43:38.740
been done. You know, those studies will probably never be done. So again, what do I, what is it,
00:43:43.780
how does it translate into actual advice along very much the lines of what you're saying? I,
00:43:49.560
you know, obviously if you're at a higher risk, I told, I talked about the grayscale of risk,
00:43:53.960
you know, I say, fine, go ahead and get your scan. And those would be things like family history,
00:43:58.000
exposure history, some particular reason that you suspect that you have a higher risk of getting
00:44:05.040
cancer. Secondly, I almost certainly advise people to do, if they're going to do a scan,
00:44:10.800
I advise them, even if they have a positive somewhere or the other, I advise them to get
00:44:14.860
an orthogonal test. By an orthogonal test, I say to them, well, okay, you've gotten the scan,
00:44:20.180
you've gotten this, let's try to see if you're also positive, if you also pick it up, for instance,
00:44:25.980
with the cell-free DNA, because two completely different tests are unlikely to have the same
00:44:31.340
type 1 error, obviously. Then, if that's still not satisfactory, I say, well, let's get at least
00:44:37.620
another scan six months later to see. And the number of people who balk at that is enormous.
00:44:43.020
People will say, no, no, I just want to get tested. And I just remind them that study after study
00:44:48.180
after study has shown that invasive tests, now if it was a superficial thing, like someone found a
00:44:54.380
spot in their skin and it's a simple skin biopsy, fine, I'll say, yes, fair enough,
00:44:59.300
go and do a simple skin biopsy. But if it's deep in the liver or it's somewhere in the lung and
00:45:03.340
there's a chance of puncturing the lung or bleeding out from the liver, I'll say, well,
00:45:08.200
there are real risks here. Do you want to really take the risks? I quantify those risks and then
00:45:13.380
give them all the information and ultimately, of course, let them make the decision themselves.
00:45:17.200
Right. Well, what do we actually know about dormancy or kind of the minimal residual disease
00:45:24.920
of somebody who's had cancer and is in something like remission? How close are we detecting
00:45:30.460
those states reliably? And how do you think about that in this picture of having or not having
00:45:36.560
cancer? So that's a very good question. So you've pinpointed the right population now. So this is
00:45:43.080
the population that I'm most interested in, I think most serious cancer biologists are
00:45:48.680
most interested in, which is you've had cancer, you've got into remission with first-line
00:45:53.620
therapy, and now we know that your cancer had some suggestion or there is a general
00:45:59.180
suggestion from the population that your cancer or your type of cancer is likely to relapse.
00:46:04.200
Can we monitor you for potentially what you're calling minimal residual disease?
00:46:08.720
By minimal residual disease, it means by all visible tests, you don't seem to have cancer,
00:46:18.440
But in fact, there is some cancer lurking in your body.
00:46:22.640
We may not know if it's growing out in the same site where it was originally found.
00:46:28.940
The most important thing about minimal residual disease is to think about it as a tool, not
00:46:34.520
By tool, I mean, we now are using minimal residual disease to see if you can use early
00:46:42.480
treatment, once minimal residual disease has been detected, to use early treatment in a
00:46:49.580
In other words, let's say, you know, Jim and Tim both unfortunately develop myeloma, both
00:46:58.880
These therapies obviously all have liabilities.
00:47:03.440
So we stop the chemotherapy. We say, you've finished with that. And we watch. And Jim does not develop minimal residual disease. In other words, let's say his cell-free DNA comes back over and over again, and there's no sign of recurrent myeloma in Jim. Tim, on the other hand, six months later, starts to have a little blip of cell-free DNA that shows the recurrence or the presence of myeloma.
00:47:28.460
So again, remember Bayes, our old friend, what we've just done is we've shifted the
00:47:34.780
Bayesian probability, prior probability that that blip that was found in this unfortunate
00:47:44.440
And what we use that for is, we can use that for is, is we can use that as a biomarker
00:47:52.760
And we can use that for testing new therapies or potentially tried and tested therapies
00:47:58.280
now in an early setting. And that has proved to be a very good strategy. In fact, myeloma is a
00:48:04.540
disease where this has actually proved to be a particularly good strategy. And the reason behind
00:48:10.420
all of this is that minimal residual disease picks up very few cells. The chances that those cells
00:48:15.760
will acquire or have acquired resistance to second-line therapies is therefore fewer, and
00:48:21.400
therefore the chances of curing the cancer or beating the cancer completely are higher. So that
00:48:26.800
is the setting. That is exactly the setting where I do use prevention, and that's a very good
00:48:32.380
setting to use preventative therapies in. All right. Well, let's talk about treatment and
00:48:36.900
cure. Is there anything in recent years, let's say, since you wrote the first edition of your
00:48:43.640
book, where a cancer has moved from being very high mortality to effectively being cured? Has
00:48:53.440
Has there been a radical breakthrough in the last 15 years for any specific cancers?
00:48:57.420
There's several radical breakthroughs for several cancers.
00:49:00.220
So people often say, oh, you know, let's take a great global view.
00:49:03.680
The very global view is people have a very dismal view of many cancer, cancers in general.
00:49:10.780
It's a second largest killer about to become the largest killer of people in the United States.
00:49:19.720
That said, overall, mortality from cancer has been decreasing over the last 20-odd years.
00:49:26.980
So 20-odd years ago, it was 200 deaths per 100,000.
00:49:31.440
That's gone down to, what, 140 deaths per 100,000.
00:49:36.440
It's a mixture of prevention, some early detection, and some treatment.
00:49:39.720
Largely driven by prevention, some early detection, some treatment.
00:49:48.520
Immunotherapy, everyone's heard about immunotherapy, using your own immune system to direct it
00:49:53.840
against cancer, using ways to, you know, cancer cells have mechanisms to conceal themselves
00:50:00.900
These medicines take those cloaks away or they make the immune system point towards
00:50:09.320
These have been radically effective for some cancers.
00:50:13.280
You know, I used to have a bet when I was a fellow that we will never have cures of advanced stage lung cancer in my lifetime.
00:50:23.780
So now there are the word cure is a complicated word.
00:50:27.580
I rarely use it because, you know, sometimes, you know, 10 years later, something might relapse and come back.
00:50:33.600
But in lung cancer, for instance, non-small cell lung cancer, we're seeing a situation where some patients and we don't know which patients and why.
00:50:42.680
but some patients, about 20% of the patients are living out five years when they're given these
00:50:48.020
immunotherapy drugs. Bladder cancer is another example where there's been a lot of progress on
00:50:53.180
immunotherapy. We talked a little bit about breast cancer, you know, breast cancer with
00:50:58.240
advanced therapies, some immunological therapies, some antibody therapies. Again, we're seeing
00:51:04.320
cases in which people are living 5, 10, 15 years after their initial diagnosis of breast cancer.
00:51:10.660
And by 5-2-3, I don't mean sort of, these are real dignified years.
00:51:18.360
A couple of more examples, myeloma is a multiple myeloma.
00:51:21.920
You know, if you plot the survival rate of multiple myeloma based on what year you were
00:51:26.380
diagnosed, I know I'm using the word survival rate, but I'm using it in a very specific
00:51:31.420
But if you plot that in 1990, 95, 2000, 2005, every five years, people diagnosed with multiple
00:51:38.640
bieloma, same stage, live longer and longer. And the last one I'll mention is the one that
00:51:44.880
sort of the story of where the story of chemotherapy begins, and that's acute lymphoid
00:51:50.080
leukemia in children, ALL in children. So by the 1980s, 80 to 90% of children with ALL were being
00:51:59.800
cured by very toxic but conventional chemotherapy. But that still left about 10 to 15% of children
00:52:06.640
who were called relapsed, refractory. They had relapsed and they were refractory to chemotherapy.
00:52:13.420
There are now new treatments. They're called CAR T-cells or T-cell treatments. This is a T-cell
00:52:18.320
that's been weaponized to kill that cancer cell. And we're seeing cure rates in these patients.
00:52:24.000
So again, five-year survival after therapy of around 50% to 60%, maybe a little bit larger,
00:52:31.240
a little bit more than that. For some cancers, quite a few cancers, I would say, we've seen
00:52:36.540
radical changes in treatment and potential cures. I've heard that CAR-T therapy has been very good
00:52:44.680
with blood cancers, but it's been challenged against solid tumors. Is that true? And if so,
00:52:50.920
what is it about tumors that poses a special obstacle? So first of all, it's true. CAR-T
00:52:57.980
therapies have been very successful in liquid tumors. In fact, I'm very involved in the field.
00:53:05.000
I made one of the first CAR-Ts in India for against lymphoblastic leukemia, ALL, that same
00:53:11.780
disease. I've made CAR-Ts against other forms of leukemia as well. So the sad answer is we don't
00:53:17.540
know. There's something different about liquid tumors and solid tumors, something in the so-called
00:53:22.740
microenvironment. Remember I said tumors don't grow in a vacuum. There are seeds that are
00:53:28.920
surrounded by soil. And in the case of solid tumors, there's a lot of soil. They're surrounded
00:53:35.160
by themselves or each other. They're surrounded by blood vessels. They're surrounded by immune
00:53:39.400
cells. They're surrounded by supportive cells that support their growth. So this thing is
00:53:46.080
called the microenvironment of a tumor. And for some reason, CAR T cells don't seem to be able
00:53:51.940
to penetrate the microenvironment of a solid tumor and deliver their kill. So that's changing
00:53:59.760
over time. We're actually combining CAR T cells with therapies that can make the microenvironment
00:54:06.460
less resistant. But for some reason, CAR T cells have never really fully grown to show their
00:54:13.040
promise in solid tumors. Now, cancer drugs, there might be some exceptions here, but my understanding
00:54:19.160
is that just as a class of drugs, they're notoriously expensive. As treatment becomes
00:54:25.100
more personalized and sophisticated, is this synonymous with them growing more expensive
00:54:31.740
still? And what are the social or scientific implications of this?
00:54:37.880
Well, the social and scientific implications are well known. I mean, we are spending billions of
00:54:42.680
dollars of money on cancer drugs, and they're expensive. Mostly, and we'll talk about why
00:54:48.940
they're expensive in a second. But the good news in some ways is that some of these drugs,
00:54:54.560
some of the most very promising drugs, like the immunotherapies that I talked about,
00:54:59.140
are going to come off patent soon. And generic versions are going to be available. There's
00:55:04.380
always a fight between legacy companies that have made the drug that will keep saying that
00:55:11.260
the original drug is actually still the better drug. That's mostly not true. The FDA ensures
00:55:16.000
is that the generic drug that emerges, which is usually one-tenth the cost or should be one-tenth
00:55:21.700
the cost, is actually just as effective as the pioneer drug. So that's one piece of good news.
00:55:27.120
There are many cancer drugs that are coming off patent, and that should decrease the price
00:55:32.140
dramatically, which is a reminder to us that we should be respectful of the patent cycle.
00:55:38.700
So I think it cuts both ways. We should be respectful of patents, but we should also be
00:55:43.020
respect for the patent cycle. So which means that when someone makes an invention, pours sweat,
00:55:47.680
blood, and tears into this invention, does a clinical trial, they get protected from
00:55:53.100
infringement for, depending on the particular class, for let's say 20 years. After those 20
00:55:59.460
years, these efforts to continue to extend the patent life cycle of a drug, we should be resistant
00:56:05.760
to that because they've gotten there 20 years. They've made their ample amount of money. They
00:56:10.280
should have spent that money on innovation and making new drugs. And if they haven't,
00:56:14.720
that's their problem. They should basically give in to the generics, as it were.
00:56:18.520
Sid, you must have seen this article by Catherine Ebon, who I think was in Vanity Fair maybe eight
00:56:24.960
years ago, that suggested, with a fair amount of research, that the pipeline for generic drugs
00:56:31.060
in particular, but really even the precursors of brand label drugs, was far less reliable than
00:56:38.500
anyone would hope. And I mean, if memory serves, something like 30% of generic drugs didn't even
00:56:47.460
contain the advertised compound. And there's just all kinds of, I mean, it detailed this
00:56:54.220
kind of a litany of corruption where, you know, labs in India, generic labs in India were tipped
00:56:59.200
off once a year when the FDA is going to come inspect their lab, et cetera. So there's kind
00:57:04.120
of a Potemkin village of laboratories. I mean, how aware of that problem are you? Has it been
1.00
00:57:11.440
exaggerated? And more importantly, if it was real, is it less real today?
00:57:16.660
Well, it certainly was real for a while. It's become less real. So the solution to this is
00:57:23.720
not to have spot audits, but to have continuous audits and to have continuous checks. This is not
00:57:30.760
a difficult thing to do. For instance, there are multiple mechanisms by which you can keep checking
00:57:36.060
whether a generic drug coming usually from India, from China, from South Korea, less from China
00:57:41.760
because of geopolitical reasons, but from South Korea. Sometimes they come from very diverse
00:57:47.920
sources that they actually contain the active ingredient. It's actually not hard to check this.
00:57:53.620
This is a relatively simple check. You can put it through a machine like an NMR or other kinds
00:57:59.240
machine, which will ensure that the parent drug and the generic drug actually are actually the
00:58:04.900
same. And in fact, since the so-called multiple scandals that have erupted because of this,
00:58:12.560
the typical scandal was a factory, let's say in India, would get tipped off that there's an FDA
00:58:17.880
inspection coming and all of them would just sort of clean up the factory, put on their coats and
0.99
00:58:22.040
start making the real drug as it were, and then go back to their old ways as soon as the FDA
00:58:27.180
inspector had left. So that's why continuous audits are helpful and also continuous checks,
00:58:33.500
quality QC checks made independently by an independent organization, whatever you want
00:58:37.560
to call it. And I'm very much aware of the original article in Vanity Fair that really
00:58:42.340
pointed out this as a major problem. So that's one solution, which is the genericization of
00:58:49.000
high value, high impact patented drugs should bring the cost down. The other solution, and we'll
00:58:54.840
Now switch a little bit, talking more about new technologies and potentially AI.
00:58:59.360
The other solution is, you know, part of the reason that the cost of drugs is so high is
00:59:05.540
And most pharmaceutical drugs fail because they don't have the right research apparatus.
00:59:10.740
You know, they're basically two or three reasons.
00:59:12.680
But let's say the two big reasons is that they've got the wrong target.
00:59:16.000
In other words, they're targeting the wrong protein.
00:59:17.940
Protein is the machinery that drives the cancer cell, or they've got the wrong chemical.
00:59:22.840
The chemical is not good enough to target that protein.
00:59:24.840
or the wrong biologic or protein to target the original protein.
00:59:28.960
So either they're missing the target or they're missing the protein.
00:59:31.820
And occasionally, it's because they run the wrong kind of study.
00:59:34.760
Now, what's interesting is that in the new world, we have, and I'm involved in this very
00:59:40.000
personally, so I should give that as an important caveat.
00:59:43.540
In the new world, we are making more and more drugs through a combination of virtual means
00:59:50.940
and real, you know, we don't take a virtual drug and put it into human patients. It has to be then
00:59:56.220
tested on animals and potentially then go through a human clinical trial and ultimately becomes a
01:00:00.960
real drug. But in all that, in that life cycle of the birth of a new medicine, we have new
01:00:07.460
technologies, including most importantly, perhaps AI as a new tool to make drugs, to test drugs,
01:00:15.060
to test drugs efficiently, and hopefully bring the cost of a trial down or the life cycle of a
01:00:20.220
drug down so that you can actually make cheaper, better, faster drugs.
01:00:23.720
Okay. So let's talk about AI because I know you have your own effort here, which I want to hear
01:00:27.840
about. But the context that many people will have noticed is that there was a big piece of press
01:00:34.100
some years ago when AlphaFold solved the protein folding problem. And I forget what the color on
01:00:40.920
this was. It was something like, you know, had done the equivalent of, you know, 200,000 PhD
01:00:45.240
dissertations. I mean, it's like the equivalent man hours was just ridiculous. So that obviously
0.73
01:00:52.040
suggests that AI can be helpful in finding plausible targets for medications and crafting
01:01:00.440
molecules for those targets. Obviously, there's a prospect that AI will transform radiology and
01:01:09.800
and data analysis. What is still just promise or hype at the moment? And where is AI really
01:01:19.320
making a change to outcomes for people now? So if you look across the spectrum,
01:01:26.360
I think AI has already delivered promises in some parts and in other parts is about to or
01:01:33.160
has started delivering promises. So you should really think about not one AI, there are multiple
01:01:39.160
AIs for this. We're not talking about acquired general intelligence. We're talking about what's
01:01:45.700
called neurosymbolic AI or AI that's been taught on rules and then are taught on patterns in some
01:01:52.220
cases. And we're talking about AIs that are different in each and every case. So let's again
01:01:58.240
start with prevention. So in prevention research, there's not been a lot of use of AI yet,
01:02:04.400
but it's very ripe for AI research. The reason it's very ripe for AI research is that prevention
01:02:09.480
research, again, to remind people, the kind of study that would be very helpful in prevention
01:02:14.520
would be to figure out, you know, what is your background genetics? What are you exposed to? So
01:02:19.560
what's your exposome, as people call it? What is your, you know, you can add in other things like
01:02:24.880
what is your microbiome? What is your, you know, what are other large multidimensional features
01:02:30.580
that comprise you, genetics, exposures, behaviors, diets, and so forth, and then construct, as it
01:02:38.800
were, a multidimensional version of you and ask the question, if you construct that multivectorial,
01:02:44.540
multidimensional version of you, who is likely to get a higher risk of any one cancer? So that is
01:02:51.280
a kind of problem that humans are not very good at, but AI is quite good at because it's a highly
01:02:56.080
complex multidimensional problem, and ultimately produces a correlation. It's not going to tell
01:03:01.360
you why something is causing cancer, but it's going to tell you a correlation, and then you
01:03:06.260
can do subsequent experiments to figure out why. So that's one area. The second area you identified
01:03:11.620
was in detection and in diagnosis. So again, an area that AI has played a very strong role in.
01:03:20.560
So, as you know, mammography is routinely used to detect early breast cancer, and there's a miss rate. And the miss rate is because the radiographer hasn't seen or finds a funny pattern that they miss. AI is a very good, you know, I think of it as a person whispering across your shoulder and saying, well, are you sure about that little white spot?
01:03:42.100
So it's almost like having a companion with a human being.
01:03:49.260
That's true now for screening for lung cancer in high-risk patients.
01:03:53.340
It's true for their AI modules that look at a skin lesion and make a decision whether
01:04:01.400
Is this something that people can take for granted now?
01:04:04.320
I mean, if you're going in to get any kind of medical imaging done, more or less anywhere,
01:04:10.380
let's just call it the United States. Can you safely assume that in part of the workflow of
01:04:16.380
data analysis, there is an AI component now, or is this only happening in bespoke places in the
01:04:22.300
biggest cities or in research hospitals? It's largely still in bespoke places.
01:04:27.320
Some of them are still actually in test mode, in beta mode. But the chances that this will succeed
01:04:33.360
as a companion. I often say the word diagnosis comes from the root of the word is learning
01:04:41.100
together. And this is going to be a companion mode. There are various ways you can think about
01:04:47.480
it. You can think about a triage as a triage mechanism. You can think about it as a second
01:04:51.740
opinion mechanism. But nonetheless, it's coming. I would say this is a likely given for radiology
01:05:01.620
So, you know, when you have a pathological lesion,
01:05:03.500
you put it under a microscope, you take a picture,
01:05:05.460
the pathologist says, I'm not sure if it's cancer or not.
01:05:10.660
has been trained on typically 500,000 images of a melanoma
01:05:16.000
or, you know, 500 million images of a melanoma.
01:05:27.320
So let's now move on to drug discovery and clinical trials. So those are two other areas which are very interesting and important. So in drug discovery, this is what we do. This is what Manus AI does. That's my company. I co-founded it with Ujwal Singh and Reid Hoffman.
01:05:44.240
And what we do, the crucial insights that we discovered was that if you want to do drug
01:05:49.380
discovery with AI, you have to teach AI the rules of medicinal chemistry.
01:06:01.940
And when you find a pocket, they'll find a way to insert or create a drug for that pocket.
01:06:12.100
And the other problem is that there are not enough exemplars.
01:06:15.820
So just like I said, there are 500,000 specimens of myeloma sitting in some bank somewhere.
01:06:21.520
And AI can look at those and learn the images, look at those images and learn the pattern
01:06:25.400
and look at a new one and say, that's a myeloma or not a myeloma.
01:06:29.920
There's not enough teaching data on generative chemistry, on true drug generation.
01:06:40.200
it's difficult to do, but it's a very important thing. The second arena is target discovery. So I
01:06:45.780
just said, you know, every drug, every medicine works by binding to a target, usually a protein.
01:06:51.360
So on one hand, you know, AI can help with target discovery. Manus doesn't do that. We have
01:06:56.660
collaborators who do that. There are many academic labs who do that. So finding out, you know,
01:07:00.740
what's a good protein to inhibit, to activate, to, you know, what's the, the analogy is lock and key.
01:07:06.620
In one case, how do we find the locks, and then how do we find the keys?
01:07:11.300
So the way you find it, the AI is very helpful in finding the locks because the lock involves
01:07:15.880
taking, again, very multidimensional cellular data and finding out where the lock is, turning
01:07:22.280
the lock, turning of which will stop the cancer from growing.
01:07:25.860
So there's a big role for AI in target discovery.
01:07:29.620
Second role for AI, as I said, in molecular discovery, still to be fully proven out, but
01:07:34.800
as you may know, for non-cancerous diseases, a recent spate of papers have shown that for
01:07:40.240
non-cancerous diseases, and in fact, some for some cancerous diseases as well, you can use AI to
01:07:45.200
build a molecule or to find a molecule. One is a search algorithm and another is a build algorithm,
01:07:50.180
but you can use AI to find a molecule that actually would turn the lock, the key in the
01:07:54.800
right way. Finally, final note is about clinical trials. Clinical trials can be extraordinarily
01:07:59.360
powered by AI. AI can, for instance, to give you one example, go into hospital records under safety,
01:08:06.020
under HIPAA rules, et cetera, et cetera, go into hospital records and identify patients who are
01:08:10.520
likely to benefit from a particular trial or a particular drug. So that's a data search problem.
01:08:16.340
In fact, we already have language models that are able to scrape the web or scrape electronic
01:08:22.280
medical records and find the right kinds of patients. And secondly, we have things called
01:08:27.580
adaptive trials. Adaptive trials are trials in which basically over time, the trial itself evolves.
01:08:34.000
More people are moved to one arm or to another arm to ensure that there's a balance as we move
01:08:38.700
along. And the trial learns as it moves along. And that's another, as soon as you use the word
01:08:44.000
learning, it means that if human beings can learn that, then certainly AI can learn that.
01:08:48.660
So when you think about AI in medicine, in particular, if you think about different AIs
01:08:54.080
doing different things for different aspects of medicine, all of which are very empowering and
01:09:00.100
powerful. When you think about the future, do you think about it more or less being a foregone
01:09:06.900
conclusion that at some point cancer will be fully behind us and we'll look back on all of
01:09:14.680
those generations of people who lived in a world where cancer was more or less untreatable and
01:09:20.460
and just, I mean, we'll just feel the poignancy appropriate to that. It's just a contingent fact
01:09:27.140
of history that at one point we had no idea how to stop this thing, and now it's not even a thing.
01:09:34.120
I mean, are you anticipating that kind of future in some, you know, how surprised would you be not
01:09:40.620
to achieve a future like that, you know, if we don't destroy ourselves some other way in the next
01:09:50.100
But look, as far as cancer is concerned, I'm an optimist.
01:09:53.380
I've seen in my own lifetime, many cancers slowly transform into from incurable acute
01:10:01.900
diseases to chronic diseases and some to curable diseases.
01:10:08.860
Breast cancer, I talked about there, you know, somewhere between you and me and the people
01:10:15.100
in the studio. There's a woman who has breast cancer who's now lived her life with dignity and
01:10:20.840
with a good quality of life 15 years since her original diagnosis, 20 years since her original
01:10:26.960
diagnosis. A century ago, she would have been miserable with undergoing surgeries for advanced
01:10:33.260
breast cancer and having all the consequences of those surgeries. But some cancers we've had a
01:10:38.300
very hard time with. Acute leukemia, myeloid leukemia, not the kind that most of the children
01:10:44.040
get. But acute myeloid leukemia, we've had a very hard time with. So a lot of my own research has
01:10:48.940
been how to find new ways of treating acute myeloid leukemia that's different from the
01:10:54.020
current paradigm. In fact, we use CRISPR technology to try to beat acute myeloid leukemia.
01:11:00.000
Recent data, for instance, there's a big stir in the world because a very old target of cancer
01:11:08.220
called RAS. The gene is called RAS, a new medicine from a company called Revolution Medicine,
01:11:13.880
and in fact, several other companies are making them. A company called Revolution Medicine made
01:11:17.420
a RAS inhibitor. RAS is one of these so-called four horsemen of death of cancer, one of those
01:11:23.080
genes that keeps coming up across multiple cancers. And you can imagine RAS as driving
01:11:30.560
the cancer with its whip. This medicine essentially holds the whip and stops it from moving. And
01:11:37.300
therefore the cancer is no longer able to respond to that malignant signal from RAS.
01:11:43.000
In the clinical trial for pancreatic cancer, as you know, pancreatic cancer is a terrible disease.
01:11:47.560
We haven't been able to budge mortality from pancreatic cancer for decades. In a clinical
01:11:53.180
trial for pancreatic cancer, randomized patients who were given this drug lived 13 months versus
01:12:02.140
patients who were treated with standard therapy who lived six months. And you could say to yourself,
01:12:06.180
well, who cares, 13 months. But that's how cancer therapies evolve. The way cancer therapies
01:12:13.080
evolve these days is that it's a little bit like driving the first crampon into a mountain.
01:12:21.880
The first crampon is not the way you climb. You're not going to climb the mountain with
01:12:24.960
the first crampon. But the first crampon gives you a foothold on what the problem is. And it's
01:12:30.500
the first crampon that allows you to then put the second crampon on. So the second crampon in this
01:12:35.260
cases to say, well, okay, the RAS gene became blocked or stopped. What happened? Why did these
01:12:42.420
patients relapse after 13 months? So you put the next cramp on and then you put the next,
01:12:47.540
and this is how basically bit by bit by bit, many, many other terrible diseases, myeloma was a good
01:12:53.860
example. This is how these cancers became more and more chronic diseases and in some cases became
01:13:00.320
curable. So the big story is not that we increased the survival of patients by six months
01:13:09.260
with this new RAS inhibitor. The big story is that we planted the first crampon in 20 years
01:13:15.080
against pancreatic cancer, which was really not planted before. So do I think that cancer is going
01:13:20.940
to go away from human biology, from human history forever? No, that's impossible. As cancer is a
01:13:27.420
disease of aging. We can change our lifestyle. We can decrease the incidence. There are medicines
01:13:33.040
that will, for instance, obesity is related to cancer. So as the population hopefully becomes
01:13:38.860
less obese because of other medicines, lifestyle changes, healthy changes, yes, we will decrease
01:13:44.080
the risk of getting cancer. Obviously, you know that the decrease in smoking has been the largest
01:13:50.160
driver of the decrease in cancer mortality ever in human history. So do I think it'll go away
01:13:55.380
completely? No. Some people get cancer because of just plain old bad luck, and that will still
01:14:01.980
remain. Do I think that many of those cancers will become treatable in the future? Yes. Will
01:14:07.140
there be some that will remain sort of frustratingly out of our reach? Yes, but that number will be
01:14:12.780
fewer and fewer. All right. Finally, a political question that I gestured at in some disparaging
01:14:19.480
remark about RFK Jr. earlier. What is the Trump administration doing to medical science at the
01:14:25.680
moment? I mean, it was much, the vandalism was much discussed initially. Has much of it been
01:14:34.700
significantly rolled back quietly, or are we still in a state of just lighting everything on fire for
01:14:41.840
no good reason and defunding essential medical science and putting ideologues and conspiracy
01:14:49.700
nuts in charge of everything. I mean, just how much damage has been done and how much damage
01:14:54.600
has been quietly repaired, if any? Well, a lot of damage was done initially,
01:15:00.760
and that's evident by the fact that there's been, you know, across the entire academic
01:15:07.660
establishment and certainly across the drug development establishment, there's been
01:15:11.880
seeds of chaos were and have been planted. And that's been a huge problem. I can say
01:15:18.820
very globally speaking, and by globally, I mean in the United States in terms of institutions,
01:15:26.320
severe funding cuts to the CDC, threatened funding cuts to many other organizations,
01:15:31.320
and certainly no increases in budgetary increases, increased scrutiny of research where scrutiny was
01:15:39.740
not required, lack of scrutiny of research where scrutiny is required. So it's really been a kind
01:15:46.500
of, I would say, I would describe it as a minefield. That said, I think cancer is something
01:15:54.760
that affects all populations, Republicans, Democrats, regardless of your political leanings
01:16:01.480
and political spectrum. And the public has spoken. I think increasing that the public is speaking,
01:16:06.440
the public has spoken. It's speaking about other diseases. It's speaking about the fact that
01:16:11.020
in a highly civilized country, we have a thousand odd cases of measles. And there are deaths from
01:16:21.780
measles because people have become reluctant to give the measles vaccine. So without pointing
01:16:29.340
individual fingers, I would say the administration has been relatively anti-science, but also that
01:16:36.540
the voice of the people, and by that I mean the larger American people, has always been, in some
01:16:42.540
sense, a voice of sanity and a voice that says science has to be restored in order for us to
01:16:48.600
make progress. We just have to restore scientists. Trust in science has to be built. Some of the
01:16:55.100
fault is the fault of scientists themselves. They've locked ourselves up in ivory towers
01:17:01.600
that didn't fully communicate with the public about what's going on. Drug prices are a big issue
01:17:10.220
and people feel the pinch of drug prices and they feel very annoyed that pharmaceutical companies
01:17:15.020
are racketeering their way through all of this.
01:17:17.780
But slowly over time, I think some of this will be repaired,
01:17:29.200
But rebuilding that institution takes years and years of work.
01:17:32.320
It's one fell swoop of a pen, and the USAID is gone.
01:17:36.700
One swoop of a pen, and half the CDC has been dispatched.
01:17:40.920
Restoring these people, because people lose their training,
01:17:43.500
they lose their jobs, they lose interest in coming back to the job and so forth. So restoring the
01:17:48.600
ecosystem will take years and years and years. I'm very concerned about the fate of US science.
01:17:54.860
And I'm also concerned about the fate of US innovation. Of course, we're doing a lot of
01:17:59.400
innovation in AI, but just to give you a number that will maybe stick in your head, in 2020,
01:18:05.760
the United States in license, in other words, brought in from China about $5 billion of drugs.
01:18:12.900
in 2025, that number will be $60 to $70 billion, expected to be $60 billion. So in other words,
01:18:20.460
most of the medicines that we're getting in the United States are really medicines that are
01:18:25.540
emerging from Chinese biotech companies and are being imported by the United States.
01:18:31.960
And we've just taken the most valuable thing that the United States produces, which is innovation.
01:18:37.480
I'm not even talking about the pharmaceutical industry in particular. We've taken the most
01:18:41.200
valuable thing the United States produces and made it and hobbled it. And that is going to be
01:18:47.780
very, very difficult to repair. I thought one of the indelible lessons from the COVID pandemic was
01:18:54.380
that we needed to onshore many of these supply chain essentials. Well, in fact, we've offshored
01:19:00.460
them. We didn't learn that lesson. You remember we discussed this exactly in a previous podcast
01:19:07.800
about onshoring of medical resources, onshoring of medical technologies, onshoring of manufacture,
01:19:15.200
really. I'll just give you another surprising fact. I have a great fear that some supply chain
01:19:21.960
disruption of some kind, and I can name many different kinds, will suddenly cause hospitals
01:19:26.880
not to have intravenous saline. Saline is sterile salt and water. And you cannot go into a hospital,
01:19:35.060
you cannot perform surgery. You cannot do a simple procedure without sterile saline.
01:19:41.760
And if that runs out, you can imagine the whole hospital with all this very fancy medicine,
01:19:47.560
$10 million MRI machines, et cetera, none of it will work. So absolutely, we need to make sure
01:19:55.140
the supply chains are resilient, they're robust. And the best way to make them resilient and robust,
01:19:59.900
of course, is to onshore them. It keeps manufacturing. The administration keeps saying,
01:20:04.200
we want more manufacturing jobs in the United States. Well, here's an area. Make more manufacturing
01:20:09.920
jobs for life-saving either medicines or life-saving pharmaceutical products and ensure that the
01:20:17.180
supply chain is not disrupted. Well, Sid, it's always great to get you on the podcast. Thank
01:20:21.860
you for the work you're doing and just the clarity of your communication around this issue.
01:20:26.400
My pleasure. Thank you. And thank you for your podcast, which always does a great service to
01:20:30.540
science. Oh, nice. Nice. Well, again, that reminded people, the new edition of The Emperor
01:20:36.260
of All Maladies is out there, four new chapters. It's a great read, and it won the Pulitzer for a
01:20:42.400
reason. And I hope to get you back here. The door's always open. When you feel like the story
01:20:49.260
has changed in any important way, whether it's with respect to AI or anything else, please give
01:20:54.060
it a knock and come back on. Yeah, I think the next time we'll come back probably is when AI