Skin Lumps and Bumps in Dogs

During the course of grooming, playing with, or handling your dog, you may discover a lump or bump or or beneath the skin. To learn what it may be, see this table on lumps or bumps or or beneath the skin.

  • Abscess: A painful collection of pus at the site of a bite or puncture wound.
  • Basal cell tumor: Solitary nodule, usually on a narrow base or stalk. Round, normally hairless, and may be ulcerated. Found on the head, neck, and shoulders of older dogs.
  • Ceruminous gland adenoma: A pinkish-white dome-shaped growth in the ear canal less than 1 centimeter in size. May become ulcerated and infected.
  • Epidermal inclusion cyst: A firm lump beneath the skin. May discharge cheesy material and become infected.
  • Hematoma: A collection of clotted blood beneath the skin; often involves the ear flaps.
  • Histiocytoma: Rapidly growing dome-shaped (buttonlike) growth found anywhere on the body, usually in young adults.
  • Lipoma: Smooth round or oblong growth beneath the skin; feels somewhat soft.
  • Mast cell tumor: Solitary or multiple growths usually found on the trunk, perineum, and legs. More prevalent in certain breeds, including Boxers, Golden Retrievers, Bulldogs, and Boston Terriers.
  • Melanoma: A brown or black pigmented nodule found in areas of dark skin. Growths in mouth and nailbeds usually are malignant.
  • Perianal gland tumor: A solitary or multinodular growth in the perineum around the anus. Occurs most often in older intact males.
  • Sebaceous adenoma: Also called sebaceous cyst. Smooth, pink, wartlike growth less than 1 inch (2.5 cm) in diameter. Most common on the eyelids and limbs. Occurs in older individuals (average age 10). Very common in Poodles and Cocker Spaniels.
  • Skin papillomas: These grow out from the skin and may look like a wart. Not painful or dangerous
  • Soft-tissue sarcomas: Ill-defined or well-demarcated masses of varying size and location. Often slow growing.
  • Squamous cell carcinoma: A nonhealing gray or reddish-looking ulcer found on the belly, scrotum, feet, legs, lips, or nose. May resemble a cauliflowerlike growth.
  • Transmissible venereal tumors: Ulcerated, often multiple cauliflower-like growths on the genitalia of both sexes.

This article is excerpted from “Dog Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.