Liz Buchanan BVSc MRCVS
Hello - For simplification, there are two types of skin lesion - the ones where the cell structure has changed, as in cancer, benign cancer, hyperplasia (overgrowth) etc, and the ones brought about by the inflammatory response e.g. a reaction to a foreign body, allergy, to the body's own tissue (auto-immune) or to bacteria . yeast / viruses etc. Where it gets confusing, is that of course cancerous growths can become inflamed and inflammatory growths could have cancer cells in there too. I'm afraid that I can't see the pictures at time of writing, but I'm not too upset about that,because it's virtually impossible to tell by looking at a lump what sort of cells are in a lump. As a rough guide, inflammation tends to itch and cancer tends not to, but as I said, mixtures occur so this isn't such a good rule that anyone would rely on it. Anyway, in the case you describe, it sounds as though things cleared up with some treatment but became worse again. If your dog didn't scratch or bite the area for long enough, perhaps if superficial products were used (we don't tend to give oral antibiotics for these these days) and something to stop any itching, the area might have chance to clear. However, this does rely on a robust treatment regeme such that self-trauma is not an option - a collar alone can be helpful but occasionally pain relief and anti-inflammatories, in order that the skin simply doesn't itch, might be the way forward. Skin is only skin-deep, it is true, but it is also crucial; lots of the body's nerve-endings are there and whether cancerous or not, it can tend to hurt. Patient nursing until the area is completely healed is often advised. Every time it flares up again, the prospect of improving things gets a little harder, so we would strongly recommend veterinary involvement. They may also decide to biopsy.