Cholangiocarcinoma with Multiple Organ Metastasis in a Captive Puma (Puma concolor)

A 17-year-old captive male puma (Puma concolor) died after presenting anorexia, vomiting, weight loss and lethargy. At necropsy, the right middle lobe of the liver was severely affected by a tumor, and small tumor nodules were disseminated throughout the other lobes. The numerous tumor nodules were also found in the lung, stomach, kidney, heart and diaphragm, which were growing together, suspiciously metastatic, projecting, 5 to 40 mm in diameter and tawny to white in color. Histopathologically, the tumor was composed of prominent papillary-acinar structures and the cells had a resemblance to the biliary epithelium. Immunohistochemically, the tumor cells were strongly reactive for cytokeratin and CD10 and were negative for carcinoembryonic antigen, fetoprotein and hepatocyte paraffin-1. Taken together, the tumor was diagnosed as cholangiocarcinoma. This is the first case report of a cholangiocarcinoma in the puma.