Clinical presentation, risk factors and staging systems of cholangiocarcinoma.

Cholangiocarcinoma (CCA) is the second most common primary liver tumour. Intra-hepatic CCA develops within the liver parenchyma while extrahepatic CCA involves the biliary tree within the hepatoduodenal ligament. Hilar CCA are also called Klatskin tumour. The CCA incidence has increased worldwide over the last years, but there are also geographic differences, with focus in Asian countries. Known risk factors are primary sclerosing cholangitis (PSC), hepatolithiasis, Caroli's disease, hepatitis B and C infection, liver flukes, cirrhosis, diabetes, obesity, alcohol consumption and probably tobacco smoking. Patients with early CCA have only little discomfort, but can later show episodes with jaundice and other non-specific tumour symptoms. For the staging of the disease different classifications are available, which consider various factors like tumour size, location, regional lymph nodes, metastasis, vascular involvement and tumour marker.