Cholangiocarcinoma is an uncommon tumor arising from the biliary tract. It can be stratified into two categories based on location, intrahepatic and extrahepatic. In the United States, approximately 4,000-5,000 cases of cholangiocarcinoma are diagnosed each year. The most common location is at the bifurcation of the common hepatic duct and is classified as extrahepatic, also known as a Klatskin tumor. Approximately 60-80% of tumors are found in this perihilar location. A history of primary sclerosing cholangitis confers 10% lifetime risk of developing cholangiocarcinoma. Other known risk factors include ulcerative colitis, liver fluke infestations, hepatolithiasis, thorotrast exposure and choledochal cysts. Cholecystectomy decreases the risk. Most patients are lymph node positive at diagnosis, approaching 55-60%, and less than half are resectable at diagnosis.