Cholangiocarcinoma in tissues of a free-ranging Eurasian brown bear (Ursus arctos arctos). (a) Liver. Two large masses with adherence to the peritoneum. Disrupting approximately 60% of the parenchyma were multiple 2–40-mm masses that extended into all lobes. The masses were white to yellow-brown, firm, well delineated, and protruded above the capsule of the liver. Inset: Section of the liver tumor with central necrosis characterized by friable, yellow, and cavitated foci. (b) Multiple 2–30-mm umbilicated masses in the gallbladder. (c) Elbows. The right elbow is normal. The left elbow joint is disrupted by the neoplasia with infiltration and necrosis of the olecranon bone.