Liz Buchanan BVSc MRCVS
Hello! If you type 'lump' into the search-bar on the Blog page of this site, you will find most of what I like to say about lumps in dogs (my name is Liz Buchanan), as well as some excellent, more recent articles by other people. This one may, for example, be a histiocytoma (a benign lump, disappears on its own) or a wart, or some kind of cancer, which might or might not be sinister. The fact that it isn't painful makes an abscess e.g. due to a foreign body or trauma, much less likely. Your vet may recommend a wait-and-see approach - this is often for a finite amount of time, however - or removal or a biopsy, depending on what appears to be most likely (given the close-up appearance and the patient's age and signalment). I hope that that helps - please do let us know what happens next.