Prostate Cancer
This is probably an idiotic idea, but please hear me out and then tell my why I'm wrong. Assuming a drug like atezolizumab works in only a small percentage of patients. Let's say we know that if patient A has success with the drug and we juxtapose him with a patient B who failed to respond can we assume that the difference in these patients is in their immune systems and not the biology of their cancers.
If blood types could be matched why couldn't you remove enough immune cells, on the order of say the provenge model and then replicate and infuse them into patient B.