On the topic of interesting Physics contributing to new cancer therapies, there is also Boron Neutron Capture Therapy (https://www.neutrontherapeutics.com/about-bnct/). I gather the gist of it is that it builds up boron isotopes around a tumour, then bombards it with neutrons that mostly pass through the body but interact far more with the boron isotopes. Energetic particles are emitted, have a low range, and hopefully kill just the cancer cells. Apparently all in less sessions than with X-ray or proton therapy.

Disclaimer: I am not a doctor or medical physicist, I’m just fortunate enough to briefly use a machine intended for this purpose in separate nuclear physics studies. I believe BNCT has been done before with reactor sources of neutrons, but for some reason not as a standard treatment and there’s only one left in Taiwan for this purpose. The new development, afaik, is the ability to use accelerator neutron sources for this. Would love it if anybody knows more!