I have had a couple of gerbils go in for surgery recently. A couple of months ago my little slate girl Zoey had a lump on her ear that was removed. I sent it in for lab work. It turned out to a melnoma (can't spell). She is perfect fine. The vet joked that now she is half doberman.
Our four year boy Buddy developed a abcess on his scent gland that got infected. The vet though at first it was tumor but it was a nasty abcess. He had to have stitches. The doctor prescribed Metacam antibiotic for his recovery. He came through great. healing nicely. Play with his boys. He is an older schimmel. His orange faded into white as he got older. The only indication of orange is at the base of his tail. He is "our" boy.