So... As a cancer patient myself going through chemo, I'll take the chemo over the cancer any day if the week. While some chemo treatments suck, it typically depends on what stage you're at, if you're curable, your comorbidities, and your personal genetics. I can say without any doubt whatsoever I'm alive right now because of chemo. Reducing the tumor allowed me to eat, which has kept me from wasting away into death. Survival times tend to increase with treatment, however quality of life of that survival time is reduced drastically for some people which I believe is what your point is not accurately reflecting, but again it's different for every single patient. I'm young, otherwise healthy, and I'm tolerating the chemo far better than expected with a far better response than average. I'm halfway through average expected survival time and if I live 2 more years I'll be drastically beating the odds. Right now that looks possible for me and that's because of the cancer treatment. There's also been a groundswell of new standard treatments, premeds, and novel treatments as better understanding of the disease in the past 10 years is just starting to bear fruit. If you look at survival rates of some common cancers in the United States many of them are downright not terrible odds of surviving through unless you catch them very late in their development.