Hi @wandrnrose7! I think rats make better pets than hamsters but I'm a guinea pig owner and lifelong fan of the little piggies. My sister and nephew have always owned and loved rats though. I think the tumors could also just be genetics. They've had quite a few rats and they do seem to get tumors often. I'm sorry about the losses of your pets. It is never easy to lose a pet. Sadly, not many vets (here anyway) want to even deal with little critters. 🐀