Spontaneous cholangiocarcinoma in a ring-tailed lemur (Lemur catta).

A cholangiocarcinoma in the liver with metastasis to the regional lymph nodes was found in a male ring-tailed lemur (Lemur catta). The liver was partially replaced by a gray-white, coarsely lobulated mass. Microscopically, the tumor consisted of well circumscribed lobules of anaplastic, low cuboidal cells occasionally arranged in duct-like structures. The tumor did not involve the gallbladder.