Lump/Growth on Cat's Tail

I have a 20 year old cat that has a growth/lump on the base of her tail. The vet says it's nothing, but had a name for it. I moved out of state since then and wondered if anyone would know what this is?
mswla

It could be a few things. Has the cat been indoors all it's life? Did he asperate it to see if he got anything out?

My cat has a cyst on the side of his head close to the lower portion of the ear penna. I always though it was a mole, but it started growing and I got worried. At his checkup the tech stuck a needle in it and got all this water out. She said it was almost fully drained and that it would drain more and be gone. Well it didn't drain all the way *lol* so it's still there. My mom asked our dog's vet if he had any advice and he said surgery would be the best option because he could drain it but it would keep coming back. He said it wasn't harmful though.

Does anyone know what kind of surgery would have to be performed to remove this? Would it be just like getting a mole burnt off our bodies or would it be a bit more complicated? I am so wary of my cat being tranq-ed I have held off on getting his teeth cleaned. I'll probably have then do his teeth and the cyst in one fell swoop.

Well, any swelling is by definition a tumor (so says my cat vet book). It could be an abcess (an infection under the skin), it could be an abnormal but benign growth of body tissue or it could be cancer. Ms Kitty - did the vet do a biopsy? It's the only way I know of to tell if its malignant or not.