The advantage of THC / CBD is that they have comparatively benign side effects and even help the side effects of chemo and radiation. That being said, there's a lot of pie-in-the-sky stuff around weed and I wouldn't take it too seriously other than a quality of life thing. However, CBD especially is pretty harmless so if you can get your hands on it I doubt it would hurt. I recommended it for my grandfather who has some sort of late stage brain tumor due to lack of side effects, but he elected to forego any treatment not related to quality of life so I don't have any first hand anecdote to share. I think there is a CBD clinical trial but I'm not aware of anything very scientific outside of in vitro or animal studies. If you PM me I can put you in touch with some researchers.