Retrospective study of canine cutaneous tumors in Korea

Over the 42 month period from January 2003 to June2006, a total of 2,952 canine biopsy specimens werereceived from the Veterinary Medical Teaching Hospitalof Seoul National University and from veterinary practitionersacross the nation. Out of these, 748 (25.34%) cases werediagnosed as canine cutaneous tumors in the Departmentof Veterinary Pathology, College of Veterinary Medicine,Seoul National University, Korea. Thirty-eight differenttypes of cutaneous tumors were identified and categorizedinto epithelial and melanocytic tumors (56.95%), mesenchymaltumors (38.90%), and hematopoietic tumors (4.14%)located in the skin. Among these, 69.25% were benign and30.74% were malignant. The top ten most frequentlydiagnosed cutaneous tumors were epidermal and follicularcysts (12.70%), lipoma (11.36%), mast cell tumors (8.82%),cutaneous histiocytoma (7.49%), basal cell tumors (6.82%),sebaceous gland adenoma (6.68%), sebaceous glandhyperplasia (5.08%), hepatoid gland adenoma (3.61%),apocrine adenocarcinoma (3.07%), and fibroma (2.81%),in order of prevalence. They comprised 68.45% of allcutaneous tumors. These top ten cutaneous tumors weredistributed on the trunk (30.08%), head and neck(20.9%), extremities (19.14%), anal and perianal area(8.59%), and tail (3.91%). The age of the dogs with the tenmost frequent tumors had a mean age of 8.3 years, with arange of 2 months to 19 years. When all types of tumorswere considered together in the entire population, therewas no difference in incidence according to sex.

Hepatocellular adenoma in a Eurasian otter (Lutra lutra)

A 7-year-old female Eurasian otter (Lutra lutra) at the Seoul Grand Park, Korea, died after displaying depression, anorexia, weight loss and rough skin for several days. At necropsy, a solitary friable round mass, which was approximately 12 x 9 x 5 cm and mottled dark red and yellow, was found bulging from the right hepatic lobe. Microscopically, the nonencapsulated, poorly circumscribed mass was composed of solid sheets of neoplastic hepatocytes. In addition, numerous small tan foci, ranging from 0.5 to 1.0 cm in diameter, were evenly scattered throughout the pancreatic tissue. These foci were found to be nonencapsulated, well-demarcated hyperplastic nodules of the exocrine pancreatic gland. We observed neither intrahepatic nor extrahepatic metastases. Based on the gross and microscopic changes, we diagnosed the animal as having a hepatocellular adenoma accompanied by exocrine pancreatic nodular hyperplasia.

Multilobular tumor of the mandible in a Pekingese dog

Multilobular tumor of bone detected in a 2.5-year-old male Pekingese dog is reported. Grossly, the neoplasm consisted of multiple, variably sized, gritty, grayish-white to yellow nodules separated by thick collagenous septa. Histologically, these nodules contained multiple lobules of irregularly shaped and sized islands of well-differentiated osteoid and cartilage, separated by anastomosing fibrovascular septa. Chondrocytes and osteocytes were observed in the lacunae and in more osseous islands in the lobule, respectively. These lobules were surrounded by mesenchymal spindle cells. Mitotic figures were not evident. The neoplastic pattern was consistent with that of a multilobular bone tumor. Diagnosis was based on gross and light microscopic findings. The cause of this neoplasm was not determined.