In the spring my dog had a fast growing tumor they said was subcutaneous carcinoma, stage 3. He had surgery to have it removed but when they opened him up the tumor had dissolved, there was nothing there. The doctor removed all the irregular tissue and a small low grade mast cell tumor that had been undetected. Tests said they had clear margins - my dog was cancer free - no chemo or radiation required. 4 months later small bumps appeared under his neck, behind his ears, on his head and all over his body - lab tests showed mast cell cancer. He was put on prednisone, Benadryl, and Pepcid and the bumps got smaller. We took him to an oncologist who said she doesn’t know what will happen and we will just have to see. She gave me 3 treatment options saying it is all 50/50 chance it will work. No staging info. He has taken palladium for about 6 weeks and some bumps have gotten bigger and dark and he has weakness in his back legs making his mobility a little difficult. She recommends adding iv chemo 2x a month - but still not sure this will do anything - maybe it will, maybe it won’t. I don’t know what to do? The lameness in his back legs makes me want to just keep him on prednisone and Benydril and maybe add an organic diet. Any advice?