Biliary Tract Cancer

Biliary tract cancers encompass tumors of the gallbladder, extrahepatic bile ducts, and ampulla of Vater. In the United States, biliary tract cancer is the fifth most common malignant neoplasm of the digestive tract, accounting for about 3,700 deaths per year. The gallbladder is the primary subsite for 40% of biliary tract cancers, followed by the extrahepatic bile ducts (33%), ampulla of Vater (20%), and unspecified subsite (8%). Gallbladder cancer occurs twice as often in women than men, while other biliary tumors are more common in men. Risk of gallbladder cancer is elevated in Amerindians, including the Pima Indians in the United States and the Mapuches in Chile, and in certain Hispanic populations. While a significant fraction of these tumors are related to underlying gallstones (cholelithiasis), information on other risk factors is limited, due to the rarity of the tumors, the often rapidly fatal course, and small number of epidemiologic studies.