It is a rare type of tumor that has its origin in the biliary epithelium. It was initially described by Durand-Fardel in 1840. This tumor can affect any part of the biliary tract and be divided according to the affected location of the biliary tree into intrahepatic, perihilar, or biliary bifurcation and extrahepatic or distal. The tumor that affects the hilar region was described by Gerald Klatskin in 1965 and is named after him today. The involvement of biliary bifurcation is the most common, representing \( \raisebox{1ex}{$2$}\!\left/ \!\raisebox{-1ex}{$3$}\right. \) of the cases. Surgical resection is the most effective mode of treatment and the only chance of cure. However, many patients already present with advanced disease at the time of diagnosis. In cases where surgical resection is not possible, patients have a survival of 6 months to 1 year and end up dying from liver failure or cholangitis resulting from biliary obstruction, despite palliative measures.