Biliary stricture due to hepatocellular carcinoma: diagnosis by bile duct brushing cytology

Bile duct brushing cytology is a useful technique in the diagnosis of malignant biliary strictures. Adenocarcinoma is the usual type of carcinoma diagnosed in these brushing specimens. This report details the bile duct brushing cytology findings in an unusual case of hepatocellular carcinoma which presented with obstructive jaundice due to invasion of the biliary tract. A striking feature of the brushing was the prominent capillary vascular pattern associated with the tumor cells. This is a cytologic feature which has been noted in fine-needle aspirates of hepatocellular carcinoma as well, and is distinct from the expected findings in adenocarcinoma.