Biliary Tract Cancer

This chapter reviews the epidemiology of biliary tract cancer. Many etiologic leads for biliary tract cancer have come from clinical observations, autopsy series, and descriptive epidemiologic studies. While a significant fraction of these tumors are related to gallstones (cholelithiasis), information on other risk factors is limited, due to the rarity of the tumors, the often rapidly fatal course, and the small number of epidemiologic studies conducted to date. Because the three anatomic categories of biliary tract cancer have distinct epidemiologic patterns and molecular changes, including somatic mutations and loss of heterozygosity (LOH), it has been suggested that the causal factors vary by subsite.