You don't actually have to run that many trials before a 0.02% liklihood event happens by chance.
Considering how many of these get conducted and the odds are often better than 50/50, I expect multiple trials have cured everyone.
If colorectal cancers in 2nd or 3rd stage actually had a fifty-fifty chance of spontaneous remission in the real world, the disease would be a lot less scary than it is.
They don't. Spontaneous remission does happen, but isn't common. The chance that a 12-patient trial produces spontaneous remission in all 12 patients in a truly random fashion, is much smaller than 1:5000.
And the GP actually mentioned it. But everyone reacting to him still addresses the 1:5000 value. It is a nice example of anchoring as described by Daniel Kahneman - here is a number, let's cling to it.
THat's how it works in clinical trials. I didn't make my statement out of ignorance- I worked adjacent to trials for decades and have seen all sorts of claims of results that didn't hold up to scrutiny.