Is there a Vet out there? Growth on my dog :-(

[Guest]

My 8 yr old Min Pin has a lil black roundish growth/mass on his backside, which I initially thought was a bug bite of some sort, but it has gotten bigger since it 1st appeared 8 months or so ago, but has stopped growing. When it is touched, he has absolutely no pain or emotion towards the touch. I took him to the vet yesterday, who said that it doesn't "appear" to be harmful, but that he cant tell for sure by just looking at it under his microscope. The dr. brushed it off as not dangerous from what he can tell. His suggestion was to either wait and see if anything develops or to have a biopsy done. I didn't really like that he gave me those choices. This vet has a good reputation, but the wide spectrum of the 2 choices really did bother me. The biopsy will be very expensive, but if needed, I would of course come up with a way to pay for this potential operation. My question is: Does this sound like something typical in dogs and could it simply be a cosmetic thing, or does it sound like it could be dangerous?

[guest]

please post your dogs medical records with a description of the cytology microscopic slide