Bile duct cancer is a rare disease in which cancer cells form within the passageways that transport bile between the liver and small intestine. The three kinds of bile duct cancer are named according to the location in which they are found and include distal bile duct cancer, perihilar bile duct cancer and intrahepatic bile duct cancer. Almost all such cancers are cholangiocarcinomas, though some other forms that can develop include lymphomas, sarcomas and small cell cancers. Importantly, tumors that form in the bile ducts are not always cancerous. Treatments for bile duct cancer are dependent upon the location, extent and formation of the disease but primarily include surgery, radiation therapy and chemotherapy - with clinical trials also an option.