I seem to remember reading about using Malaria to fight cancer many years ago. People that had experienced Malaria rarely had cancer. IIRC, the real work was the high fever. Another system used machinery to raise the blood temp. and thus the core temp. Of course the high temps also boil the brain (and strain the heck out of the heart), but everything has a side effect. And of course, in my case, no one would notice if my brain had been boiled.