Sneezing and a possible tumor

Question
My pet rat had a respitory infection about a year ago.  I took her to the vet and she was put on meds but she still sneezes and has red stuff around her nose at times.  Also we noticed the other day that she has a lump the size of a ping pong ball under her right arm it seems soft.  Could this be a tumor and if so how expensive can it get to have it removed?  

Answer
Hi there, sounds like your rat has a mammory tumour. These can be removed pretty easily but the sooner the better as they will grow as big as tennis balls and by then the only option will be to get the rat euthanised. It is not that expensive but I cant give you a price, contact a vet that is experienced in small animal surgery. As for the red stuff, its a mucous they secrete during times of stress. She may need another course of stronger antibiotics if she has another infection. Good luck