Cholangiocarcinoma is a group of cancers that begin in the bile ducts. Bile ducts are branched tubes that connect the liver and gallbladder to the small intestine. They carry bile, which is a fluid that helps the body digest the fats in food. Bile is produced in the liver and stored in the gallbladder before being released in the small intestine after a person eats. See Bile Duct Cancer for signs, symptoms and treatments.