Cholangiocarcinoma is a type of malignant tumor that affects the biliary system. It can arise anywhere in the bile ducts, manifesting itself as obstructive jaundice. It has an annual incidence of 1-2 cases per 100,000 people. One variety of the disease, the Klatskin tumor, occurs in the hepatic hilum and is characterized by poor prognosis. Generally, cholangiocarcinomas are slow-growing tumors with late metastases. Localized tumors are treated surgically, but intervention is discouraged when they are extensive. The disease affects both sexes, but most cases occur in patients aged over 60 years. Primary sclerosing cholangitis, chronic biliary infection, and choledochal cysts are associated with an increased risk of cholangiocarcinoma.