Mucocutaneous plasmacytomas in dogs: 75 cases (1980-1987).

Mucocutaneous plasmacytomas were diagnosed in 75 dogs. Medical records and communication with owners and referring veterinarians provided information regarding location and description of the tumor, clinicopathologic data, treatment, and postoperative status of the dogs. Males and females were equally represented, and most dogs were aged adults (mean, 9.7 years). Tumors developed most commonly in the mouth, on the feet or trunk, and in the ears. Plasmacytomas were confined to the skin and mucosa in 70 dogs. Two dogs had disseminated lymphoid neoplasia, and 1 dog developed cutaneous plasmacytoma during clinical remission of lymphosarcoma. Two dogs had multiple myeloma, which was diagnosed concurrently or within a few weeks of diagnosis of the cutaneous tumor. Multiple plasmacytomas were found in 10 dogs but were not associated with clinical signs of generalized disease. Tumors did not recur after surgical excision. Clinicopathologic values, when determined, were normal in all dogs with localized plasmacytomas.