Pathology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey
Combined hepatocellular and cholangiocellular carcinoma (combined HCC-CC) is a tumor with hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CC) in same neoplastic tissue. This primary liver tumor is quite rare in dogs.
The aim of the case is histopathological investigation of combined HCC-CC and its metastasis.
A fourteen-year-old Husky male dog was brought for necropsy after being euthanized due to general condition disorders like weakness, lethargy and anorexia. After necropsy was performed, tissues were processed routinely and stained with haematoxylin-eosin.
Macroscopically, focal irregular areas in varying sizes with pale white color drew attention especially in the margins of all hepatic lobes. Masses with similar characteristics were also found in lobes of lungs, right kidney and epicardium of heart. Microscopically, both cuboidal intrahepatic bile duct cells and polygonal hepatocytes drew attention in same areas. All cells showed pleomorphism. The tumor was diagnosed as combined HCC-CC. Also, cirrhosis and necrosis were seen remarkably in the liver. The neoplastic cells with similar characteristics were also found in lungs, kidney and heart. Neoplastic cells in the lungs and kidney had invasive character. But in the heart, neoplastic cells were limited to vessel lumens and muscle bundles. Degenerative, necrotic and inflammatory changes were also prominent in these organs.
Combined HCC-CC is an uncommon tumor. Also, kidney and heart metastases are rarely reported in HCC and CC tumors. At the same time, the appearance of cirrhosis in liver and necrosis in metastatic organs were remarkable for clinical pathology.