This is basically what you should do for any pet if you see a tumor... Go to the vet and try to ask for his/her opinion. I had to do this with one of my old dogs...She had a cancerous tumor and her vet said that if she wasn't put to sleep or go through surgery, she would die a painful death...and there was no point in the latter, because if it was cancerous it would just keep coming back(run on sentence, got a second and third opinion mind you). So my late German Sheperd spent the last two days of her life getting belly rubs, eating her favorite treats for meals, and just getting spoiled rotten before we put her to sleep...Do what you see best. It's better to put her to sleep while you still can if it's malignant before the tumor gets bigger and starts giving your rat too much pain. I know you'll do what you see as the best for your rat.
Good luck!
Regards,
Danny(Human), Michelle(Himalayan), and Elly(Black Hooded)
