Bile Duct Cancer (Cholangiocarcinoma) Explained

This page is for anyone who wants a plain overview of bile duct cancer. It covers what it is, the types, what raises risk, the symptoms, and how it is treated.

Bile ducts are thin tubes. They carry bile from the liver and gallbladder into the small intestine, where bile helps digest fat. Bile duct cancer, also called cholangiocarcinoma, starts in the cells lining these tubes. It is uncommon: the American Cancer Society says about 8,000 people in the US are diagnosed each year. Nearly all cases are adenocarcinomas, a type that starts in gland cells.

Doctors classify bile duct cancer by where it starts, because location affects symptoms, treatment, and surgical options.

• Intrahepatic cancer starts in the smaller bile duct branches inside the liver itself. It makes up about 1 in 10 cases.
• Perihilar cancer, sometimes called a Klatskin tumor, starts where the ducts from the left and right sides of the liver join together.
• Distal cancer starts farther along the bile duct, closer to where it passes through the pancreas and empties into the small intestine.

Several conditions that damage or inflame the bile ducts raise cancer risk over time:

• Primary sclerosing cholangitis, a disease that inflames the bile ducts and causes scar tissue to form.
• Bile duct stones and choledochal cysts, both of which cause long-term irritation in the ducts.
• Liver fluke infection, caught from eating undercooked fish, a major reason bile duct cancer is far more common in Southeast Asia.
• Cirrhosis and chronic hepatitis B or C infection.
• Inflammatory bowel disease, including ulcerative colitis and Crohn's disease.
• Inherited conditions, including Lynch syndrome and cystic fibrosis.

Diabetes, obesity, and older age also raise risk. The average age at diagnosis in the US is in the 70s. Having a risk factor does not mean you will get bile duct cancer. Many people diagnosed have no clear risk factor at all.

Bile duct cancer often causes no symptoms until a tumor grows large enough to block bile flow. Once that happens, symptoms tend to appear together:

• Jaundice, a yellowing of the skin and eyes, from bile backing up into the bloodstream.
• Itching, caused by the same buildup in the skin.
• Pale, greasy, bulky stools, because bile is not reaching the intestine.
• Dark urine, as the body tries to remove the excess through the kidneys instead.
• Pain below the right ribs, appetite loss, weight loss, and sometimes fever.

These symptoms are far more often caused by something other than bile duct cancer, most commonly gallstones or hepatitis. Even so, jaundice needs medical evaluation right away. It points to a problem, most often in the liver or bile ducts, that needs to be identified.

Surgery to remove the tumor offers the best chance of cure. The American Cancer Society says surgery offers the only realistic chance of cure. It is only an option when imaging suggests the whole tumor can be removed. These are complex operations, usually done by experienced teams at major cancer centers.

Some cancer cannot be fully removed. Targeted drugs may be an option for some tumors with certain gene changes, so testing the tumor matters. Ask your team about other treatment choices. A stent or a bypass operation can relieve a blocked bile duct, even when cure is not possible. This can meaningfully ease symptoms and improve day-to-day comfort.

• Which type of bile duct cancer do I have, based on its location?
• Is surgery possible for my tumor, and what would it involve?
• Has my tumor been tested for specific genetic features that could guide targeted therapy?
• If a cure is not possible, what can be done to relieve symptoms like jaundice or itching?

• American Cancer Society — What Is Bile Duct Cancer?
• American Cancer Society — Bile Duct Cancer Risk Factors
• American Cancer Society — Signs and Symptoms of Bile Duct Cancer