Of course, that is beside the point. One of the most effective treatments remains a series of prolonged dry or water fasts. ~10 and ~40 days respectively. But because no one can patent it or make $3M a year in kickbacks, I doubt it will ever be known to the mainstream in my lifetime.
There are clinical trials of fasting in cancer patients. These have been designed by careful and ethical scientists and doctors. They are looking currently at whether fasting can improve the efficacy or tolerance of chemotherapy.
It is frankly stupid to take an already malnourished individual and make them fast for 40 days.
The only times people have not been as successful as others is when fasting was preceded by chemotherapy/radiation which frankly destroy the body and for the most part is a death sentence one way or another.
And you are flat out wrong about your last point. Fasting is the biggest gift you can give your body, including and especially when it appears weaker due to a disease.
Just as you're skeptical of research in the area, I'm skeptical of people claiming to have seen "hundreds of people" cured of diseases by something as simple as fasting.
What are the best sources you have seen to support this? I have seen articles via Google, but I'd like to see more sources. (Writing this comment sitting next to a cancer fighter on a 48-hr chemo session.)