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  • You may have heard the expression

  • knowledge is power.”

  • Well, today we're going to give you more power

  • to control your diet and lifestyle

  • by giving you the facts.

  • Welcome to the Nutrition Facts Podcast.

  • I'm your host, Dr. Michael Greger.

  • Did you know that most chemotherapy drugs

  • are approved by the FDA without evidence of benefit

  • on survival or quality of life? Here's our first story.

  • Over the next few decades, the number of new cancer cases

  • will continue to skyrocket. Are we winning the war on cancer?

  • Sadly, in general, no,

  • this despite the introduction of hundreds of new anticancer drugs.

  • The war on cancer has been likened to the war on terror.

  • No matter how many drone strikes you do, it's nearly impossible

  • to kill all the bad guys, and no matter how precise the bombing,

  • one must always consider the collateral damage.

  • The toxicity from cancer therapy can be debilitating,

  • and not just health-wise. There's also the "financial toxicity."

  • Patented anticancer drugs are priced at up to

  • nearly a thousand dollars a day.

  • Even with health insurance, the average cost to patients

  • for stage IV breast cancer, for example, can run $190,000.

  • It's bad enough to be fighting for your life without bankrupting

  • your family at the same time – a problem still common to this day.

  • Who can forget the apocryphal story of Walter White, working two jobs

  • with health insurance and still could not afford the cancer care?

  • Now, not everyone is willing to start their own meth lab,

  • but many are willing to go for broke.

  • A large proportion of cancer patients reported their willingness

  • to declare bankruptcy or sell their homes to pay for treatment.

  • I mean, look, aren't the high prices justified if new and innovative

  • treatments offer significant benefits to patients?

  • But you may be shocked to find out that many

  • FDA-approved cancer drugs may lack clinical benefit.

  • Well, then how did they become FDA-approved?

  • Most approvals of cancer drugs are based on flimsy

  • or untested surrogate endpoints,

  • and postmarketing studies rarely validate the efficacy and safety

  • of these drugs on patient centered endpoints.

  • Let me explain what that means.

  • New chemo drugs are increasingly approved just based on

  • so-called surrogate endpoints, which means instead of looking at what

  • we really care aboutsurvival or quality of lifethey approve

  • drugs based on things like response rate, tumor shrinkage.

  • But who cares if a tumor shrinks if it doesn't actually extend

  • your quantity or quality of life?

  • It's kind of counterintuitive, but just seeing a tumor shrink

  • on a CT scan or MRI is not necessarily correlated

  • with improvements in survival or symptoms.

  • In fact, most studies that have actually followed people out

  • found low correlations with survival.

  • The most recent comprehensive analysis found 90% of studies

  • of such validation trials found little correlation with overall survival.

  • Of 36 new chemo drugs approved by the FDA based on these kind

  • of surrogate endpoints, once they were actually

  • put to the test in the real world,

  • only 1 in 7 was actually shown to extend life,

  • and half explicitly flopped,

  • and the rest remain untested, revealing that most cancer drug

  • approvals have not been shown to, or do not, improve

  • clinically relevant endpoints.

  • Exorbitant drug prices are bad enough for treatments that work,

  • but charging vulnerable patients for drugs without evidence that

  • they actually improve patients survival and quality of life

  • is unconscionable.

  • Why doesn't the FDA require proof that chemo drugs

  • actually benefit patients before approving them?

  • Drug companies say that requiring randomized, controlled trials

  • with meaningful measures would take too long,

  • but the study time reduction using surrogate endpoints

  • rather than overall survival is estimated at just 11 months.

  • So instead of it taking 7.3 years to come to market on average,

  • it would take 8.2 years.

  • Yes, look, we want to get these drugs out as soon as possible,

  • but only if they're actually going to help people.

  • Do cancer drugs improve survival or quality of life?

  • You don't need to know, according to our broken regulatory system.

  • And things aren't much better over in Europe.

  • A systematic evaluation of chemo drug approvals showed

  • that most entered the market without evidence of benefit

  • on survival or quality of life.

  • And even years later, there was still no conclusive evidence

  • that these drugs offered any benefit, and when they did,

  • the gains were often marginal.

  • That's why you see editorials in the Journal of the

  • National Cancer Institute referencing Hans Christian Andersen,

  • the author of the tale of "The Emperor's New Clothes."

  • The studies all converge on a singular conclusion:

  • only a minority of new cancer drugs approved by US and European

  • regulatory authorities in recent years deliver clinically meaningful benefits

  • to patients. In fact, some cancer- related deaths may be hastened,

  • or even caused, by the toxic effects of chemotherapy

  • rather than the cancer itself.

  • Based on a review of tens of thousands of cancer patients, in as many as 27%

  • of cases the cancer treatment itself caused or hastened death.

  • Okay, but it might be worth that risk if the potential benefit

  • is large enough. And that's the subject of my next video,

  • "How Much Does Chemotherapy Improve Survival?"

  • Though we often hear new cancer drugs described as game-changing

  • breakthroughs, most afford much more modest benefits.

  • In my last video, I quoted a recent editorial in the

  • Journal of the National Cancer Institute suggesting that the majority

  • of new cancer drugs don't deliver clinically meaningful benefits at all.

  • At least when they are later proven to be ineffective,

  • they're pulled from the market, right?

  • No! Even when postmarket studies show the new drugs to have

  • no clinically meaningful benefit compared to not just older drugs

  • but compared to nothing, compared to a sugar pill,

  • most chemo drugs retain FDA approval and remain on the market,

  • even at the same ridiculous prices. In fact, the most expensive drug

  • they looked at, the one costing $169,836 a year,

  • did not improve overall survival at all, and actually worsened quality of life.

  • $169,000 just to make you feel worse with no benefit.

  • Why pay a penny for a treatment that doesn't actually help?

  • And even when they do improve survival,

  • what does that actually mean?

  • Currently, the trend is for Big Pharma to design large trials that may detect

  • statistically significant, but often trivial,

  • differences in survival endpoints.

  • For example, check out this famous trial.

  • Adding this second drug, erlotinib, to gemcitabine for advanced

  • pancreatic cancer significantly prolonged overall survival.

  • Yeah, they suffered more side- effects, but we're not just talking

  • about tumor shrinkage. They lived significantly longer.

  • The placebo group only lived 5.91 months, whereas

  • the added drug group survived all the way to 6.24 months?

  • Wait a second. They only lived a third of a month longer?

  • That's just 10 days.

  • All the side-effects and expense for an average of just 10 days?

  • That's why doctors shouldn't use the statistical jargon ---

  • significant improvement in survival ---

  • while informing patients about benefits of new treatment.

  • When patients hear the word "survival,"

  • they're not thinking about a week and a half. If you put

  • all the new chemo drugs together approved over the last dozen years,

  • the average overall survival benefit is 2.1 months.

  • Now look, two months is two months, I don't want to downplay that, but

  • time and again, surveys have indicated that patients expect much more.

  • Incredibly, about three-quarters of patients with metastatic lung

  • or colorectal cancer did not report understanding

  • that their chemo was not at all likely to cure their cancer.

  • I mean, that's the primary treatment, but the chemo's not curative;

  • it's just eking out a few extra weeks or months.

  • Why weren't the majority of patients told that?

  • It's not that they were being over-optimistic,

  • explained the researcher. They were under the mistaken belief

  • that the treatment offered a chance of cure when it in fact didn't.

  • That deprives patients of the opportunity

  • to weigh the risks and benefits and make their own decisions

  • about their own body.

  • If you ask cancer patients, most want at least half a year

  • to stomach the side-effects, which suggests that most

  • cancer patients might not choose chemotherapy

  • if they knew how little they'd actually benefit.

  • But look, everyone's different. One patient they interviewed

  • said living even one week longer would be worth it;

  • whereas another said they wouldn't even want to do chemo

  • for two extra years of life; they wouldn't want

  • anything to interfere with the quality of the time they had left.

  • Either way, people deserve to know the truth.

  • I find it telling that oncologists and cancer nurses themselves

  • express less willingness to accept intensive chemotherapy,

  • given the associated toxicities.

  • Most chemo drugs are cytotoxic, meaning they work by killing off

  • cancer cells, but they also kill off some healthy cells

  • as collateral damage, which is why they can damage

  • our nerves, cause irreversible heart failure,

  • slough off the linings of our gut, or damage your immune system.

  • Drug companies frequently downplay the risks, though, for example,

  • describing this breast cancer drug as having acceptable side-effect

  • profiles for most patients, or this pancreatic cancer drug as having

  • a manageable and mostly reversible safety profile.

  • These were studies published in top medical journals.

  • Naturally, readers would take these statements to be true.

  • However, if you actually look at the data,

  • the number of serious, even life- threatening side effects was double,

  • or even five times higher on the new breast cancer drug.

  • And the manageable and mostly reversible side-effects

  • evidently weren't referring to those who were killed by the drug.

  • I like how they even included like a cheat sheet.

  • Acceptable toxicity. Acceptable to whom?

  • Manageable? Serious events and deaths can never

  • be considered manageable.

  • And feasible? Who would sign up for a drug whose toxicity

  • could only be described as feasible?

  • Favorable? Compared to what?

  • Tolerable? That's for the patient to decide.

  • And any drug that kills people can hardly be considered safe.

  • Still, patients may very well consider it worth the risk.

  • For some cancers, we've made tremendous strides.

  • Testicular cancer, for example.

  • There is greater than a one in three chance that chemotherapy

  • could enable you to survive at least to the five-year mark.

  • The same with Hodgkin's disease, a relatively rare form of lymphoma.

  • But even when researchers tried to err on the side

  • of over-estimating the benefit, for most common cancers

  • colon, lung, breast, and prostate

  • the chances appear to me more like 1 or 2 percent.

  • We would love it if you could share with us your stories

  • about reinventing your health through evidence-based nutrition.

  • Go to nutritionfacts.org/testimonials.

  • We may share it on our social media to help inspire others.

  • To see any graphs, charts, graphics, images, or studies mentioned here,

  • please go to the Nutrition Facts Podcast landing page.

  • There you'll find all the detailed information you need

  • plus, links to all of the sources we cite for each of these topics.

  • For a timely text on the pathogens that cause pandemics,

  • order the e-book, audiobook, or hard copy

  • of my last book, “How to Survive a Pandemic”.

  • For recipes, check out my second-to-last book,

  • myHow Not to Diet Cookbook”.

  • It's beautifully designed with more than 100 recipes

  • for delicious and nutritious meals.

  • And all the proceeds I receive from the sales

  • of all my books goes to charity.

  • NutritionFacts.org is a nonprofit, science-based public service,

  • where you can sign up for free daily updates

  • on the latest in nutrition research via bite-sized videos and articles.

  • Everything on the website is free.

  • There's no ads, no corporate sponsorship.

  • It's strictly non-commercial. I'm not selling anything.

  • I just put it up as a public service, as a labor of love,

  • as a tribute to my grandmother,

  • whose own life was saved with evidence-based nutrition.

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Podcast: How Effective Is Chemotherapy?

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    林宜悉 發佈於 2022 年 11 月 10 日
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