Liz Buchanan BVSc MRCVS
Hello! My first concern for this lump is not necessarily the type of cell involved, but that the lump itself appears to be in a position to be rubbed, to scrape against things, to bleed and to become infected, not to mention being potentially very painful in that position. Licking is a sign of pain and irritation and also further damages / spreads around the cells being licked. The cells involved may be delicate lining cells which belong inside the dog and which would usually be hidden away safely, well-protected by mucous. In these situations, regardless of whether they are cancerous or not, spey or removal may be merited simply in order to prevent damage, pain and even perforation. My second concern is as you suggest, that some of the possibilities for this lump may be malignant / cancerous (for example, adenocarcinomas). If your vet is not certain in their own mind, then they will have a pathologist they can speak to who is used to seeing lumps such as this in the lab, and can guide them regarding the numbers and probabilities as to how many such lumps have neoplastic involvement. Your vet will also be able to see the lesion in context and tell you how urgently any work needs to be done, which may turn out to be soon.