Cytodiagnosis of extrahepatic biliary duct tumors from specimens obtained during cholangiography.

Two cases of cholangiocarcinoma of the extrahepatic biliary ducts, one case of bile duct adenoma, and one case of pancreatic carcinoma involving the common bile duct are presented to illustrate cytologic diagnoses from specimens obtained during endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography. Obtaining specimens during these procedures can be advantageous because the cells retrieved are well-preserved, surgery is not required, and patients with advanced disease can be managed conservatively once a diagnosis is rendered. Cytologic diagnosis can be difficult, since malignancies of the extrahepatic bile ducts are often well-differentiated. Cytologic findings with histologic correlation are presented to emphasize the subtle cellular features of these uncommon lesions.