Unique Cutaneous Manifestation of Nonepitheliotropic Lymphoma in Dogs

* Correspondence to: Danny W. Scott (Department of Clinical Sciences, College of Veterinary Medicine, Cornell University), Ithaca, New York 14853-6401, USA FAX +1-607-253-3534 E-mail: shb3@cornell.edu Nonepitheliotropic lymphoma (NL) is one of the most common neoplasms seen in the dog. Middle-aged to older (median age 6 to 9 years) dogs are primarily affected. There is no apparent sex predilection. Breeds reported to have an increased risk include boxer, bull mastiff, basset hound, St. Bernard, Scottish terrier, Airedale, and English bulldog. The cutaneous lesions seen with NL are multiple, widespread, firm dermal to subcutaneous nodules and plaques . Dogs with cutaneous lesions of NL typically have clinical signs of systemic involvement and multicentric disease. We have seen what seems to be a cutaneous lesion unique to dogs with NL. Although we have consulted on a number (perhaps 30) of dogs with the lesion, we have information on only 5 dogs. The dogs varied from 5 to 11 years of age, included 3 spayed females and 2 castrated males, and represented the following breeds: 2 boxers, 1 collie, 1 golden retriever, and 1 beaglecross. All dogs had clinical signs of systemic disease (poor appetite, lethargy, weight loss), and multicentric involvement (external and internal lymph nodes, liver). All dogs had multiple, widespread, firm dermal to subcutaneous nodules and plaques. All 5 dogs also had a solitary arciform (arcuate) lesion on the trunk (4 dogs) or neck (1 dog). The lesions varied from 10 cm (Fig. 1) to 50 cm (Fig. 2) in length. The lesions were firm, raised, flat-topped, 0.5 to 1 cm in depth, erythematous, and dermal in location. Interestingly, the arciform lesions were not closely-