One of his best videos.
How Much Does Chemotherapy Improve Survival?, Michael Greger M.D. FACLM, Nutrition Facts, 27 July 2022.
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. That’s $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 a 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 a 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 is 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 since they wouldn’t want anything to interfere with the quality of 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 our 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 something 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 would enable you to survive at least to the five-year mark. It’s the same with Hodgkin’s disease, a relatively rare form of lymphoma. But even when researchers tried to err on the side of overestimating the benefit, for our most common cancers—colon, lung, breast, and prostate—the chances that chemo would enable survival to the five-year mark appear to be more like 1 or 2 percent.
Every single person I know who has had chemotherapy did not survive. The side effects they endured were almost worse than the disease. For me, if I’m ever faced with it, the decision has already made itself.