Extrahepatic bile duct cancer is a rare disease in which malignant (cancer) cells form in the part of bile duct that is outside the liver.
A network of bile ducts (tubes) connects the liver and the gallbladder to the small intestine. This network begins in the liver where many small ducts collect bile, a fluid made by the liver to break down fats during digestion. The small ducts come together to form the right and left hepatic bile ducts, which lead out of the liver. The two ducts join outside the liver to become the common hepatic duct. The part of the common hepatic duct that is outside the liver is called the extrahepatic bile duct. The extrahepatic bile duct is joined by a duct from the gallbladder (which stores bile) to form the common bile duct. Bile is released from the gallbladder through the common bile duct into the small intestine when food is being digested.
Having colitis or certain liver diseases can increase the risk of developing extrahepatic bile duct cancer.
The following stages are used for extrahepatic bile duct cancer:
Stage 0 (Carcinoma in Situ) – In stage 0, abnormal cells are found in the innermost layer of tissue lining the extrahepatic bile duct. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.
Stage I – In stage I, cancer has formed. Stage I is divided into stage IA and stage IB.
Stage IA: Cancer is found in the bile duct only.
Stage IB: Cancer has spread through the wall of the bile duct.
Stage II – Stage II is divided into stage IIA and stage IIB.
Stage IIA: Cancer has spread to the liver, gallbladder, pancreas, and/or to either the right or left branch of the hepatic artery or to the right or left branch of the portal vein.
Stage IIB: Cancer has spread to nearby lymph nodes and: is found in the bile duct; or has spread through the wall of the bile duct; or has spread to the liver, gallbladder, pancreas, and/or the right or left branches of the hepatic artery or portal vein.
Stage III – In stage III, cancer has spread:
to the main portal vein or to both right and left branches of the portal vein; or
to the hepatic artery; or
to other nearby organs or tissues, such as the colon, stomach, small intestine, or abdominal wall. Cancer may have spread to nearby lymph nodes also.
Stage IV – In stage IV, cancer has spread to lymph nodes and/or organs far away from the extrahepatic bile duct
The following types of surgery are used to treat extrahepatic bile duct cancer:
Removal of the bile duct: If the tumor is small and only in the bile duct, the entire bile duct may be removed. A new duct is made by connecting the duct openings in the liver to the intestine. Lymph nodes are removed and viewed under a microscope to see if they contain cancer.
Partial hepatectomy: Removal of the part of the liver where cancer is found. The part removed may be a wedge of tissue, an entire lobe, or a larger part of the liver, along with some normal tissue around it.
Whipple procedure: A surgical procedure in which the head of the pancreas, the gallbladder, part of the stomach, part of the small intestine, and the bile duct are removed. Enough of the pancreas is left to make digestive juices and insulin.
Surgical biliary bypass: If the tumor cannot be removed but is blocking the small intestine and causing bile to build up in the gallbladder, a biliary bypass may be done. During this operation, the gallbladder or bile duct will be cut and sewn to the small intestine to create a new pathway around the blocked area. This procedure helps to relieve jaundice caused by the build-up of bile.
Stent placement: If the tumor is blocking the bile duct, a stent (a thin tube) may be placed in the duct to drain bile that has built up in the area. The stent may drain to the outside of the body or it may go around the blocked area and drain the bile into the small intestine. The doctor may place the stent during surgery or PTC, or with an endoscope.