The medical name for bile duct cancer is cholangiocarcinoma.
Your cancer type depends on:
- the type of cell that the cancer starts in
- which part of the bile duct is affected
Cells of the bile duct
The type of bile duct cancer you have tells you the type of cell that the cancer started in. Knowing this helps your doctor decide which treatment you need.
Most cancers of the bile duct start in the cells that line the bile ducts. These are called epithelial cells. This type of cancer is called adenocarcinoma (add-en-oh-car-sin-oh-ma).
There are a number of other types of bile duct cancer that develop from other types of cells within the bile duct. These types of bile duct cancer are extremely rare but include:
- squamous cell carcinoma
Where the cancer starts
Your type of bile duct cancer also depends on which part of the bile duct the cancer starts in. There are 2 main types:
- cancers that start in the bile duct outside the liver (extrahepatic bile duct cancers)
- cancers that start in the bile ducts inside the liver (intrahepatic bile duct cancers)
The gallbladder is a small organ tucked under the liver. It is a small, hollow pouch about 8cm long and 2.5cm wide and is connected to the liver and bowel by a series of tubes known as the bile ducts.
The liver makes bile which helps to break down fats from food. The gallbladder stores the bile until there are fats in the bowel that need digesting. Bile can also pass directly to the bowel from the liver. A sphincter controls the release of bile into the bowel.
Cancer of the gallbladder and bile ducts are rare in the UK. They are called biliary cancers.
Bile duct cancers are divided into 3 types depending on where they develop. Intrahepatic bile duct cancer forms inside the liver. Perihilar bile duct cancer forms just outside the liver where the right and left hepatic ducts meet. And distal bile duct cancer forms in the bile ducts that go through the pancreas to the small bowel.
Lymph nodes surround these organs and make up part of our immune system, helping us fight infections. They are often the first place cancer cells reach when they break away from a tumour.
For information about gallbladder and bile duct cancers go to cruk.org/cancer-types
Extrahepatic bile duct cancers
Extrahepatic bile duct cancers start in the bile ducts outside the liver. They can be divided into two types depending on the area they develop in:
Perihilar region bile duct cancers
These are cancers that develop just outside the liver, where the left and right hepatic ducts join together. They are also called Klatskin tumours or hilar cancers. These are the most common type of bile duct cancer. Around 6 out of 10 bile duct cancers (60%) start in the perihilar region.
Distal region bile duct cancers
These are cancers that start in the bile ducts below the perihilar region near the bowel. Around 2 in 10 bile duct cancers (20%) start in the distal region. Before surgery it may be difficult for doctors to be certain whether the cancer is in the bile duct or the pancreas.
Intrahepatic bile duct cancers
Intrahepatic bile duct cancers start inside the liver. There are a number of small bile ducts that join together inside the liver to form the left and right hepatic ducts. Around 2 in 10 bile duct cancers (20%) start in the intrahepatic bile ducts.
This type of bile duct cancer is sometimes confused with cancers called hepatocellular cancers, which start in liver cells.
Non cancerous growths in the bile duct
Non cancerous (benign) tumours can also grow in the bile duct. They include bile duct adenoma and hamartomas.