I took my Dash in to a new vet today. I already absolutely love this vet! Very knowledgeable about rats, something my last vet wasn't in spite of having a reputation as being good wth exotics. They X- rayed her chest, and the tumors that took up almost half her lungs are just pinprics now! The vet couldn't believe a rat diagnosed with lung tumors in September is even alive all this time later. The growth of the tumor on her side is slow enough that at her age it wouldn't be worth putting her through the pain of surgery, but it's not affecting her mobility or quality of life. It's about marble sized. I was given some anti inflamatories for her, but otherwise as told just keep doing what I'm doing. My little girl is nothing short of a miracle.