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.

Perihilar and distal tumors are together called extrahepatic. They sit in the drainage path, so they more often block bile and cause jaundice. Intrahepatic tumors are more often found another way. They show up because of vague belly pain, weight loss, or a scan done for some other reason.

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.

Work-up usually includes CT and MRI with MRCP, a scan that maps the bile ducts. Blood tests check liver function. They often check the marker CA 19-9 as well. You may also have an endoscopic procedure such as ERCP or endoscopic ultrasound. These use a flexible tube to reach the ducts from inside. They can take samples. If a duct is blocked, they can also place a stent, a small tube that lets bile drain again.

Getting enough tissue matters twice over. It confirms the diagnosis. It also allows molecular testing.

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. For intrahepatic and perihilar disease it is usually a partial hepatectomy, which removes part of the liver. For distal disease it is a Whipple procedure. Only a minority of people are candidates when they are diagnosed.

Being told a tumor is unresectable, meaning it cannot be removed, is not the end of treatment. It changes which treatments are on the table. It is also a reason to ask for a second opinion at a center that does high volumes of liver and bile duct surgery.

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.

Bile duct cancer has become one of the clearer examples of targeted treatment in gastrointestinal cancer. Ask whether your tumor has had next-generation sequencing, a test that reads many genes at once. Changes that have led to approved drugs include:

• FGFR2 fusions or rearrangements. Found mostly in intrahepatic tumors. Treated with FGFR inhibitors such as pemigatinib or futibatinib.
• IDH1 mutations. Also mostly intrahepatic. Treated with ivosidenib.
• Other findings, such as HER2 amplification, BRAF V600E, or high microsatellite instability. These may open trial or off-label options.

Ask when the test was sent and when it is due back. The answer can change your next line of treatment.

Some cancers cannot be removed. For those, the long-standing chemotherapy backbone is gemcitabine with cisplatin. Trials then showed that adding an immunotherapy drug improved survival. The drug is either durvalumab or pembrolizumab. Both combinations are now approved for advanced biliary tract cancer. The gain is real but modest, and not everyone is a candidate. Ask what it means in your specific case.

Other chemotherapy combinations are used after first-line treatment. These include FOLFOX. When disease is confined to the liver, local approaches are sometimes considered. These include radiation or radioembolization.

Blocked bile ducts, and the infection that follows, are the complications most likely to interrupt treatment. That infection is called cholangitis.

Cholangitis is the emergency to know about, especially if you have a stent. With quick treatment the outlook is generally good. Without it, it is poor.

• Call 911 or go to an emergency department if you have fever with shaking chills alongside pain in the upper right or upper middle of your abdomen, particularly if you also feel confused, faint or very drowsy. Do not drive yourself.
• Call your cancer team straight away, day or night, if a temperature of 100.4°F (38°C) or higher appears while you are on chemotherapy or immunotherapy. CDC treats fever during chemotherapy as a medical emergency, because it can be the only sign of an infection that becomes life-threatening quickly. If you cannot reach them quickly, go to an emergency department and tell the staff you are having cancer treatment so you are seen straight away.
• Call your care team the same day if your skin or eyes turn more yellow, your urine goes dark, or your stools turn pale — a stent may be blocked.
• Call your care team within a day or two if itching, nausea or belly pain is steadily worsening, or you cannot keep food down.

• 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
• NCI — Bile Duct Cancer (Cholangiocarcinoma) Treatment (PDQ®) Patient Version
• NCI — Bile Duct Cancer Treatment (PDQ®) Health Professional Version
• MedlinePlus — Cholangitis
• NCI — Infection and Neutropenia during Cancer Treatment
• CDC — Fever and Cancer Treatment
• FDA — pembrolizumab with chemotherapy for biliary tract cancer
• NCI drug information — pemigatinib
• NCI drug information — futibatinib
• NCI drug information — ivosidenib
• NCI drug information — durvalumab