Parakeet tumors

Question
Is there anything that can be done for tumors near the vent?  I know how to treat and get rid of the fatty tumors that parakeets get on the breast.  However, according to the vet, this one isn't a fatty tumor, but is most likely benign.  They can't remove it because it's in the skin.  It's about the size of a marble and right now doesn't seem to be impairing her ability to fly or generally enjoy her life.  But, I assume it will keep growing and hope to find out a way to stop the growth if I can't get rid of it entirely.  I'd appreciate any help you can provide.  Thanks.

Answer
Hi, Phyllis.

Hopefully, you asked the bird vet this question because he would know more so than I would...I'm not an avian vet.  I always thought "benign" meant noncancerous (being a cancer survivor myself).  Meaning this could be a cyst of some sort versus a tumor ("tumor" means cancer).  Guess I'm confused.  

Chrys