Primary liver cancer is cancer that forms in the tissues of the liver. The most common type of primary liver cancer is hepatocellular carcinoma, which occurs in the tissue of the liver. When cancer starts in other parts of the body and spreads to the liver, it is called liver metastasis. Bile duct cancer forms in the small ducts (tubes) that carry bile (fluid made by the liver that helps digest fat) between the liver and gallbladder and the intestine. Bile duct cancer is also called cholangiocarcinoma. Intrahepatic bile duct cancer is found inside the liver. Extrahepatic bile duct cancer is found outside the liver.