Extrahepatic cholangiocarcinoma is a cancer of the bile duct (a cholangiocarcinoma) outside of the liver. Similar to intrahepatic cholangiocarcinoma, risk factors are ulcerative colitis, primary sclerosing cholangitis (PSC), choledochal cysts, and parasites. Gall stones are another possible cause, since the risk is decreased by previous cholecystectomy.
Extrahepatic cholangiocarcinomas are classified by site: upper third (including hilum), middle third, and lower third. The majority occur in the upper third. Clinical behaviour depends on the site. Distal tumours are more likely to be resectable than proximal. If the tumour is not resectable, prognosis is poor. Overall, prognosis is poor.