I only brought this up as a possibility. If you have nothing to lose...It might help the RSO get to the area of the brain with cancer.

DMSO can be purchases as a liquid or a gel from Amazon or your local animal husbandry store. Don't use it unless you've read about it.
you can rub it on your body and in a little while, you'll be tasting garlic in your mouth. It is said to cross the blood/brain barrier, and I assume it would carry other stuff with it. transplant body parts are transported in a bath of DMSO.
It is used as a horse liniment because it calms and sooths strained or damaged tissue. Apply ONLY with Scrubbed hands, on a clean site. Gloves suggested.