stage IV perihilar extrahepatic bile duct cancer Stage IV is divided into stages IVA and IVB. In stage IVA, the tumor may have spread to nearby lymph nodes and has spread to one or more of the following: (1) the main part of the portal vein or both branches of the portal vein; (2) the hepatic artery; (3) the right and left hepatic ducts; (4) the right hepatic duct and the left branch of the hepatic artery or of the portal vein; and/or (5) the left hepatic duct and the right branch of the hepatic artery or of the portal vein. In stage IVB, the tumor has spread to other parts of the body, such as the liver. |