Liz Buchanan BVSc MRCVS
Hello! There are three broad types of lump that people find on their dogs' testicles. This one appears to be in the scrotum, the skin layer, and could be an inflammatory lesion as simple as a superficial spot. If a skin spot or scrape itches however, dogs can cause themselves a lot of damage / make things worse, so treatment may still be advisable. Inflammatory lesions on the skin could include fly bites, flea bites, demodex or infection in the hair follicle, and trauma. A second kind of lump or thickening to the skin in this area might be cancer, which can affect the skin or the testicle or surrounding tissues. This is much less common but we have to list it. People often feel lumps within the scrotum ie to the testicle or surrounding tissues. These can be cancerous but can also turn out to be inflammatory, or indeed to be the epipdidymis, which is normally quite marked in the dog (its the same on both sides). Your vet is the best person to consult for diagnosis; if they are suspicious, or if the lump doesn't respond to symptomatic treatment, they may reccommend a biopsy.