Please keep us posted! I know exactly what you are going through and it is rough.

From my understanding the only way to determine if a tumor is cancerous is to do a biopsy. While a vet may have a hunch that it could be cancerous there is no way to tell visually. When I asked the vet who removed the tumor from Panther she said there is no way to tell if a mass is cancerous just by looking at it. There are too many other variables that can look like cancer but be something else. Usually further testing is required.

By the way, I too am still looking into holistic treatments or vitamins. There is so much crap out there that it can be hard to weed out what is beneficial.