Cholangiocarcinoma in a Margay (Felis wiedii)

Abstract

Bile duct carcinomas have been reported in domestic cats and dogs [8], cattle and sheep [8, 111, goats [3], chickens [9], pigeons [12], various zoo animals and birds [2, 4, 6, 101. Cycasin-induced, transplantable bile duct carcinomas in hamsters have been shown to be associated with virus-like particles [7]. In man, about 4500 deaths occur each year in the United States as the result of biliary tract neoplasms In this report we describe a cholangiocarcinoma with metastases in a margay (Felis wiedii). The margay is a small, feral feline found from Mexico to southern Brazil. These animals have a crown to rump length of 45-70 centimeters and a body weight from 4 to 11 kilograms. They have been known to live more than 13 years in captivity. Cholangiocarcinomas have been diagnosed in wild Felidae [6], but this seems to be the first report of its occurrence in this species. A 12-year-old female margay had been kept as a pet for 10 years. The margay had been kept primarily indoors and fed a diet of raw lean beef and beef hearts, supplemented daily with pasteurized milk, brewer’s yeast and a calcium-phosphorus mixture. Once a month she was given oral vitamin A and intramuscular vitamin B complex. The animal died suddenly without having shown signs of clinical illness. The carcass was of a well fed animal and had a good haircoat. The oral mucous membranes and conjunctiva were extremely pale; the abdomen was moderately distended and was filled with blood. The right middle lobe of the liver was swollen, dark red and markedly hemorrhagic. The hilar part of this lobe was replaced by a white, irregular, nodular mass that contained foci of hemorrhage (fig. 1). Similar, small white lesions were in the hepatic parenchyma surrounding this mass. More distant areas of the hepatic parenchyma had an apparent increase in fibrous tissue; occasionally there were small white spots. The gallbladder was surrounded by the tumor mass, yet the wall and mucosa of the gallbladder appeared to be intact. The perihepatic lymph nodes were moderately enlarged and had distinct white tissue replacing the lymphoid tissue. Both lungs had multiple small, white, firm nodules up to 5 millimeters in diameter. Other organs and tissues were grossly normal. Microscopically, the liver mass had multiple small gland-like or duct-like structures dispersed throughout abundant fibrous stroma (fig. 2). These gland-like structures were lined by cuboidal epithelium that had various degrees of hyperchromasia and moderate numbers of mitoses. The periportal lymph nodes were exten