What Is Bile Duct Cancer?

Bile duct cancer, also known as cholangiocarcinoma, is a rare type of cancer that affects the bile ducts—thin tubes in the digestive system that run from the liver and gallbladder to the small intestine.

This cancer is usually incurable, in part because symptoms usually develop after the tumor has already spread. About 10% of people survive five years or more after diagnosis.

This article covers the symptoms and causes of bile duct cancer. You will also learn how the disease is diagnosed and treated, and what lifestyle changes could help lower your risk.

Anatomy of Biliary Duct System

Your biliary system is a network of organs, ducts, and other structures that produce, store, and transport bile—a fluid that aids in digestion.

The system starts with intrahepatic bile ducts in your liver. These branch off into larger ducts and, finally, the right and left hepatic ducts. These two ducts join outside of your liver and form the common hepatic duct.

Lower down, your cystic duct extends from your gallbladder, which is the organ that stores bile until it's needed for digestion. The common hepatic duct connects to the cystic duct to form the common bile duct, which then carries bile to the small intestine.

Bile duct cancer can develop in any part of this network.

Types of Bile Duct Cancer

The three types of bile duct cancer are defined by the location of the tumor:

• Intrahepatic bile duct cancers: Start in the smaller bile ducts inside the liver
• Perihilar bile duct cancers: Start in the hepatic hilum, the area in which the left and right hepatic ducts branch off of the liver
• Distal bile duct cancers: Found further down the bile duct, just below the gallbladder

Perihilar bile duct cancer and distal bile duct cancer are more broadly referred to as extrahepatic bile duct cancers because they develop outside of the liver.

Bile Duct Cancer Symptoms

Bile duct cancer can cause hepatitis. which is inflammation of the liver. This leads to increased blood levels of bilirubin, a yellow pigment produced by the breakdown of red blood cells.

In general, symptoms of bile duct cancer are similar to those of hepatitis and may not appear until the cancer is in a late stage.

They can include:

• Jaundice (yellowing of the skin and eyes)
• Abdominal pain just under the ribs
• Fever
• Chalky stools
• Dark, cola-colored urine
• Itchy skin
• Fatigue
• Nausea
• Loss of appetite
• Unintentional weight loss

The severity of symptoms typically depends on the location of the tumor. Tumors that develop outside the liver are likely to cause jaundice, itchy skin, dark urine, and abdominal pain. In some cases, tumors inside the liver may not cause symptoms at all.

Causes

There are numerous diseases and disorders linked to bile duct cancer, including:

• Primary sclerosing cholangitis: An inflammatory bile duct disease and the most common cause of bile duct cancer in the developing world
• Inflammatory bowel diseases: Including ulcerative colitis and Crohn's disease, both of which are closely linked to primary sclerosing cholangitis
• Chronic liver diseases: Including cirrhosis, hepatitis B, hepatitis C, and non-alcoholic fatty liver disease
• Choledochal cysts: Cysts of the bile duct that block the flow of bile
• Parasitic liver parasites: Including liver flukes, which are more common in Asia and the developing world
• Congenital abnormalities of the liver or bile ducts: Including Carroli's syndrome, Lynch syndrome II, and polycystic liver disease—all conditions that are present at birth

Risk Factors

The average age of bile duct cancer diagnosis is 70. An estimated 8,000 people in the United States are diagnosed with bile duct cancer each year, making this a rare type of cancer.

Certain groups of people are also at greater risk of bile duct cancer. For reasons not entirely clear, Latinx individuals are more likely to get the disease than other groups in the United States.

Bile duct cancer does not typically run in families, although you may be more at risk if you have a family history of it.

Obesity, smoking, and excessive alcohol use are risk factors, and this is believed to be related to the inflammatory stress these conditions place on the liver.

In many cases, the underlying cause of bile duct cancer is never found.

Diagnosis

If your healthcare provider is concerned that you could have bile duct cancer, you will have a medical history and physical examination. From there, they may order blood tests, imaging studies, and other procedures to determine the cause of your symptoms.

A diagnosis of bile duct cancer is confirmed with a biopsy of the affected tissues.

Blood Tests

Healthcare providers commonly use two blood tests to help diagnose bile duct cancer. Neither confirms the disease, but they can be helpful in the diagnostic process.

They include:

• Liver function test (LFT) is a panel of tests that measures liver enzymes. High liver enzymes are a sign of liver disease or inflammation, but that doesn't necessarily mean cancer.
• Tumor marker tests measure carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9, proteins that appear in the blood in response to liver cancer, gallbladder cancer, and other gastrointestinal cancers.

Imaging Tests

Imaging tests can help visualize the tumor and surrounding structures.

A healthcare provider may order any of these studies:

• Abdominal ultrasound: A procedure that uses high-frequency sound waves to generate images of abdominal organs and structures
• Computed tomography (CT scan): Multiple X-rays are used to create images of internal organs
• Magnetic resonance imaging (MRI scan): Powerful magnetic and radio waves create highly detailed images of internal organs
• MRI cholangiopancreatography: A specialized MRI technique using contrast dyes can detect blockages and other problems in the bile ducts, gallbladder, liver, or pancreas

Procedures

Several procedures can help healthcare providers obtain biopsy samples for lab evaluation. Examination of these samples with a microscope can confirm a bile duct cancer diagnosis.

Common procedures include:

• Endoscopic retrograde cholangiopancreatography (ERCP): A flexible tube called an endoscope is passed through the mouth and into the small intestine to access the bile duct.
• Percutaneous transhepatic cholangiography (PTC): A needle is inserted through the abdomen to access tumors in the bile duct.
• Endoscopic ultrasound: A specialized probe is inserted through the mouth or rectum to examine and take tissue samples from the bile ducts.
• Laparoscopy: This minimally invasive procedure involves making several small incisions in the abdomen to access a tumor.

The tissue sample taken during a biopsy can also be used for staging, which is a determination of how advanced the cancer is.

Staging

If you have bile duct cancer, your healthcare provider will order additional tests to determine its stage.

This may involve imaging studies, such as positron emission tomography (PET). A PET scan uses a slightly radioactive dye that "lights up" in areas where there are active cancer cells.

PET scans can also help determine whether the cancer is:

• Localized: Shows no signs of spreading
• Regional: Has spread to nearby tissues
• Distant: Has spread to distant areas of the body (metastasized)

There are five bile duct cancer stages: 0 to 4. Sub-stages further define exactly where the cancer has spread. Each advancing stage indicates more extensive metastasis.

There are slight variations in how intrahepatic, perihilar, and distal bile duct cancers are staged.

^{Source: American Cancer Society}

^{Source: American Cancer Society}

^{Source: American Cancer Society}

Genetic Profiling

Your healthcare provider may order genetic testing to see if you have a gene that causes a treatable cancer mutation. If so, you may be a candidate for targeted therapies that specifically recognize and kill these cancer cells.

Treatment

The majority of bile duct cancers are incurable because the disease is typically advanced by the time symptoms appear.

With that said, bile duct cancer is sometimes caught before it has spread and can be treated with surgery and follow-up treatment to destroy all remaining cancer cells.

If the tumor cannot be removed completely, treatment focuses on slowing its spread, reducing symptoms, extending survival, and improving overall quality of life.

Surgery

Unless the cancer is clearly too advanced for surgery, most people will undergo exploratory surgery to determine if surgical resection (removal) is possible.

This is usually performed with laparoscopy rather than open surgery. With laparoscopy, a probe is inserted through very small incisions in the abdomen to examine affected tissues.

If the tumor is localized or regional with no evidence of spread, resection may be considered based on the general health of the individual and how well their liver is functioning.

The type of surgery used can vary by the location of the tumor:

• Intrahepatic bile duct cancers: These typically require surgical resection of part of the liver (hepatectomy) along with resection of nearby lymph nodes.
• Extrahepatic bile duct cancers: These are commonly treated with a Whipple procedure, which involves removing the common bile duct along with a portion of the pancreas and small intestine. The affected extrahepatic bile duct would also be removed.

Some early-stage intrahepatic tumors are inoperable but can still be treated with a liver transplant. In such cases, chemotherapy and radiation may be used to halt the spread of cancer until a donor liver is found.

Adjuvant Therapies

Adjuvant therapies are used after surgery to destroy remaining cancer cells and prevent their return. Common cancer treatments like chemotherapy and external or internal radiation therapies are considered adjuvant therapies.

It is unclear how effective these therapies are in preventing cancer from returning. There is also controversy over when it is appropriate to use them.

Part of that stems from the fact that so few people with bile duct cancer have tumors that can be operated on. Those who do may not improve with adjuvant therapies.

At present, there is no evidence that either adjuvant chemotherapy or radiation therapy can extend survival times, even for people with early-stage bile duct cancer.

Even so, healthcare providers often recommend adjuvant therapy, since there is always a chance of remaining cancer cells after surgery.

Targeted Therapy and Immunotherapy

If genetic testing reveals that you have a specific, treatable mutation of cancer, you may be eligible for targeted therapies or immunotherapies.

These treatments slow cancer growth by strengthening your immune system so that it can attack cancer cells caused by specific genetic mutations.

Targeted therapies and immunotherapies prescribed for people whose cancer has specific genetic mutations include:

• The targeted drugs Tibsovo (ivosidenib) and Pemazyre (pemiganitib), which can stop the growth of cancer
• Immunotherapeutic agents like Keytruda (pembrolizumab) or Imfinzi (durvalumab) in combination with chemotherapy

Palliative Therapy

Palliative therapy is a form of treatment used to alleviate pain and other symptoms of late-stage disease. In people with inoperable bile duct cancer, this can take several forms:

• Pain medications, including opioid drugs like fentanyl
• Palliative radiation therapy: Primarily used to reduce the size of a tumor, to unblock a bile duct, or reduce pressure on compressed nerves
• Palliative chemotherapy delivered to the blocked bile duct via a catheter in a blood vessel to shrink the tumor
• Biliary stenting involving the placement of a tube, called a stent, in a bile duct to improve biliary flow
• Biliary bypass: A surgical procedure in which the bile duct obstruction is removed and the cut ends are sewn together
• Percutaneous tumor ablation, in which heat or electrical energy is delivered to the tumor via a needle-like conductor inserted through the skin
• Percutaneous ethanol injections, in which alcohol is injected into the tumor to shrink it and deaden the nerves that relay pain

Clinical Trials

People diagnosed with bile duct cancer are encouraged to participate in clinical trials. This can provide them access to experimental therapies that may improve outcomes.

Prognosis

Five-year survival is a common measure used to determine what percentage of people with a disease will be alive at least five years following the initial diagnosis.

The five-year survival rate for bile duct cancer is broken down by how far the cancer has spread and whether the tumor is inside the liver or not.

Generally speaking, people with extrahepatic bile duct cancer have better outcomes because the liver is less likely to be affected. The outcome tends to be poor any time cancer spreads to the liver.

It is important to remember that the disease can vary from one person to the next and that the five-year survival estimates are just that—estimates. Some people can survive longer based on their general health and the location of the tumor.

Summary

Bile duct cancer is a rare, aggressive form of cancer that is rarely diagnosed in its early stages. Late-stage symptoms depend on where the tumor is located and often mimic hepatitis.

Though several tests will be done to help diagnose suspected bile duct cancer, a biopsy is ultimately needed to confirm and stage it.

Bile cancer can be treated with surgery in some cases. In addition, treatments (chemo, radiation) are often used to prevent recurrence. When surgery is not an option, treatments are given to slow progression and improve quality of life.

Even with these efforts, survival five years after diagnosis ranges from 2% to 30%, depending on the type of bile duct cancer and how far it has spread.

A Word From Verywell

Learning that you have bile duct cancer can be overwhelming for you and those who care about you. Be open with loved ones and healthcare providers about the care you wish you to receive and how you wish to spend your time.

No matter what stage of cancer you are diagnosed with, know that you have options. If you are unsure about the diagnosis or a recommended therapy, do not hesitate to seek a second opinion from an oncologist specializing in biliary cancers.