The formation of malignant (cancer) cells in the bile ducts is an uncommon condition known as bile duct cancer. The liver, gallbladder, and small intestine are connected by a network of tubes known as ducts. This system starts in the liver, where a network of tiny ducts collects bile (a fluid made by the liver to break down fats during digestion).
The right and left hepatic ducts, which lead out of the liver, are formed by the tiny ducts coming together. Outside the liver, the two ducts merge to form the common hepatic duct. The gallbladder is connected to the common hepatic duct through the cystic duct. Bile from the liver is stored in the gallbladder via the hepatic ducts, common hepatic duct, and cystic duct.
Bile stored in the gallbladder is released after digestion and flows through the cystic duct to the common bile duct and into the small intestine. Cholangiocarcinoma is another name for bile duct cancer.
Bile duct carcinoma can be classified into two types:
- Cancer of the bile ducts within the liver is known as intrahepatic bile duct cancer. Intrahepatic bile duct malignancies make up a modest percentage of all bile duct cancers. Intrahepatic cholangiocarcinomas are another name for intrahepatic bile duct malignancies.
- Cancer of the bile ducts outside the liver is known as extrahepatic bile duct cancer. The hilum area and the distal region make up the extrahepatic bile duct. Cancer can develop in either of these areas:
- Perihilar bile duct cancer is found in the hilum region of the liver, where the right and left bile ducts meet to form the common hepatic duct. A Klatskin tumor or perihilar cholangiocarcinoma is another name for perihilar bile duct malignancy.
- Cancer of the distal bile duct: This type of cancer develops in the distal part of the bile duct. The common bile duct, which runs through the pancreas and finishes in the small intestine, makes up the distal section. Extrahepatic cholangiocarcinoma is another name for distal bile duct cancer.