system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 why is it that we always see so many new awesome ways to fight cancer and yet it seems nothing of it is ever being used?

I mean, I see articles every week here on reddit about a new way to kill cancer cells etc. And it's been like that for years and yet none of these ever seem to be used to actually treat people.
gpt
There are three main factors here.

One is that medical treatments tend to get most of their news coverage when they're in early development, since that's when they're novel.  It takes years for a new medical treatment to get from "we're pretty confident this will work" to mainstream usage, both because there are a lot of processes to follow to make sure it's actually safe and effective, and because when it's new it's really expensive and so the existing treatments continue to be used in some cases.

The second is that unless you're an oncologist, you probably have no idea what methods are actually being used to treat cancer.  Some of them are things you heard about a decade ago and now are the best choice and are used routinely, but there's no reason for you to know that.  Survival rates for almost all kinds of cancer have gone way up in the last few decades, and while some of that has been due to improved detection, a bunch of it is new treatment methods.  The 10-year prostate cancer survival rate has gone from 25% in 1971 to 84% in 2011, for instance.

The third is that cancer treatment progress is incremental.  It's incredibly rare that a new treatment or prevention method comes out and cuts the mortality rate for a kind of cancer in half or more.  More commonly, a new treatment will come out that cuts the mortality rate by, say, 2 percentage points.  For a common kind of cancer, that can be thousands of people per year that live when they would previously died, but it's not going to make that kind of cancer a non-issue.  Cancer research is largely about stacking up a bunch of advancements like that, though, so that it can incrementally become less and less deadly.