Small hard acorn like looking lump on underside of dogs tail

Question
Hi
My border collie, chow, lab X has a small (about the size of a pinky finger nail) hard lump on the underside of his tail, closer to his bum.  The lump is almost acorn like in that it is smaller on top with a bit of crust.  I took him to the Vet and she seemed a little concerned that it could be cancer, she tried to take a biopsy but it was too hard and she couldn't get any cells to test.  Should I make an appointment to get this removed or just watch it?  He has had it for about a month and a half, that I know of.  He also has a small lump that is almost wart like on his left leg, the Vet didn't seemed concerned about that one though.
I appreciate your help


Answer
Hi Jen,

Thank you for writing to me about your dog's growth.  I do think that you should have it removed.  At the same time the vet can clean his teeth and remove any other lumps, including the wart like one.   When she removes the lump at the base of his tail, ask her about removing flesh surrounging the lump, just in case it is cancer.  That way you can get all of it out.

Best of Luck,
Shelley Davis