As I told another here who spoke of cancer, if you're looking for alternative cures, research essaic tea. But of course, you would need to speak to your grandmother about it. There is no harm in using it along with western medical treatment, in fact it helps those going through chemotherapy with their side effects. There is a book on it, with the recipe and other information on the formula. I wouldn't suggest buying it premade, because you don't know the origin of each herb or if they even used the right ones.
Of course, magick is a wonderful thing and it couldn't hurt to do a healing spell. I would recommend one that you would repeat every week or day. But even the great spiritual healers of the world still used herbs and treatment along with their magickal practice and prayer.