Infiltrative lipoma in dogs.

Infiltrative lipomas, similar to those described in man, were diagnosed in 12 dogs of various breeds, sexes, and ages. The neoplasms were poorly delineated, soft enlargements in muscle and connective tissue that caused dysfunction because of mechanical interference or pressure pain. The neoplasms consisted of differentiated fat cells that had infiltrated between or replaced muscle, collagen fibers or both. Single or multiple recurrences followed surgical removal in four of eight dogs: no follow-up was possible in the other four.