LUMPS & BUMPS

There are many different types of skin masses in dogs, but some of the most common are outlined below. Keep in mind these are general guidelines, and everything varies from case to case.

Lipoma

These are usually moderately soft, round masses made up of fat cells located under normal looking skin. They are usually moveable and slow growing. Lipomas are benign fat cells, and can be removed for cosmetic reasons or can be left alone if they are not bothering the dog. Breeds such as Labradors and Miniature Schnauzers are prone to lipomas.

Sebaceous cysts

These small hairless masses grow from the skin and sometimes release cystic contents onto the skin. They can appear wart like. Some cysts remain present for years while others disappear on their own. These cysts are usually benign but can be irritating or become infected. Many owners choose to have cysts surgically removed due to their appearance. Breeds such as Poodles and Bichon Frises are prone to sebaceous cysts.

Mast Cell Tumours

These tumours can take on a variety of appearances both on and under the skin—from looking like a small ulcerated bump on the skin, to a larger mass that changes in size or colour (you won't be able to see colour changes if the mass is under the fur). Mast cell tumours are malignant, and can spread to other parts of the body such as the lymph nodes and liver. A high percentage are diagnosed on the torso, near the paws, and in the area under the tail, though they can also be in other areas, such as the neck. If a mast cell tumour is diagnosed in your dog, your vet will likely recommend surgical removal including surrounding tissue to ensure all the cancerous cells are removed. A pathologist at a veterinary lab will then examine the tissue under a microscope to determine the ‘grade’ of the tumour, which gives information as to how likely it is to spread or recur. In more serious cases, referral to a veterinary oncologist may be recommended, as the dog may require radiation or follow up treatment. Breeds such as Boxers and Pugs are prone to mast cell tumours.

A large percentage of dogs will experience some type of skin lump during their lifetime. A proactive discussion with your veterinarian will help put your mind at ease in the case of benign masses, and give your dog the best chance of successful treatment in the case of malignant masses.