Hilar Cholangiocarcinoma: Symptoms, Causes & Treatment
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: September 2026
Hilar cholangiocarcinoma — also called perihilar cholangiocarcinoma or a Klatskin tumor — is a bile duct cancer that starts where the right and left bile ducts leaving the liver join to form the common hepatic duct. It is the most common type of bile duct cancer, though still rare overall, and it most often affects adults over 50. It usually causes no symptoms at first; when the tumor blocks bile flow, symptoms such as jaundice (yellowing of skin and eyes), itching, dark urine, clay-colored stools, stomach pain, fatigue, and weight loss appear. Surgery is the main treatment and the only chance to cure the disease when all the cancer can be removed, though fewer than half of people can have surgery at diagnosis. Options also include liver transplant, radiation, radioembolization, chemotherapy, targeted therapy, immunotherapy, and palliative care.
Quick Answer
Location: where the right and left bile ducts join to form the common hepatic duct — called a Klatskin tumor
Frequency: the most common type of bile duct cancer, but rare overall; mostly adults over 50
Symptoms: often none at first; when bile is blocked — jaundice, itching, dark urine, clay-colored stools, stomach pain, fatigue, weight loss
Main risk factors: primary sclerosing cholangitis, inflammatory bowel disease, liver cirrhosis, bile duct cysts, gallbladder conditions, liver flukes (raw/undercooked fish)
Diagnosis: exam and history, ultrasound/CT/MRI/MRCP, ERCP or PTC with tissue samples, blood tests, CA 19-9 and CEA tumor markers, biopsy
Treatment: surgery is the only chance to cure (less than half qualify at diagnosis); liver transplant with radiation for select cases; biliary drainage relieves symptoms
Other options: chemotherapy, radiation, radioembolization, targeted therapy, immunotherapy, palliative care
See a doctor for any persistent symptoms that worry you
What Is Hilar Cholangiocarcinoma?
Hilar cholangiocarcinoma, also called perihilar cholangiocarcinoma or a Klatskin tumor, is a type of cancer that starts as a growth of atypical cells in the bile ducts. Bile ducts are slender tubes that carry bile — the digestive fluid the body uses to break down fat — from the liver to the small intestine.
Cholangiocarcinoma is the medical term for bile duct cancer. It is classified by location into three types:
Intrahepatic: inside the liver, in the ducts within the liver.
Hilar (perihilar, Klatskin tumor): where the right and left bile ducts join to form the common hepatic duct.
Distal: lower in the bile duct, near the small intestine and pancreas.
Bile is made in the liver and flows into the gallbladder, where it is stored until needed for digestion. While eating, the gallbladder releases bile into the bile duct, which carries it to the duodenum (the upper part of the small intestine) to help break down fat.
Hilar cholangiocarcinoma is the most common type of bile duct cancer, but it is still a rare form of cancer overall. Common symptoms include yellowing of the skin and the whites of the eyes, weight loss, stomach pain, and itching.
Hilar Cholangiocarcinoma Symptoms
Hilar cholangiocarcinoma may not cause symptoms at first. Symptoms typically happen when the cancer grows and blocks the bile ducts, preventing bile from draining from the liver into the intestine.
Jaundice: yellowing of the skin and the whites of the eyes.
Itching: persistent itching.
Dark urine: urine that looks darker than usual.
Clay-colored stools: pale, clay-colored bowel movements.
Stomach pain: abdominal discomfort or pain.
Fatigue: ongoing tiredness and low energy.
Weight loss: unintentional loss of weight.
When to see a doctor: make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.
Causes: What Causes Hilar Cholangiocarcinoma?
It is not clear what causes most hilar cholangiocarcinomas, but the cancer is often linked to long-term inflammation or injury of the bile ducts.
Hilar cholangiocarcinoma develops when cells in a bile duct get changes in their DNA. A cell's DNA contains the instructions that tell the cell how to grow and when to die. In healthy cells, these instructions keep growth under control. In cancer cells, DNA changes give faulty instructions that tell the cells to grow and divide too quickly and to keep living when typical cells would die.
The buildup of these cells can form a tumor in the bile ducts. Long-term inflammation or injury to the bile ducts — such as from primary sclerosing cholangitis or bile duct cysts — can increase the chance of having these DNA changes. The tumor can grow to invade and destroy healthy body tissue, and in time cancer cells can break away and spread to other parts of the body (metastatic cancer).
Risk Factors
Factors that may increase the risk of hilar cholangiocarcinoma include:
Primary sclerosing cholangitis: causes inflammation, hardening, and scarring of the bile ducts that can lead to cancer.
Older age: most often in adults over age 50; can develop younger in people with primary sclerosing cholangitis.
Inflammatory bowel disease: ongoing inflammation of the digestive tract increases risk.
Liver cirrhosis: scarring of the liver increases risk.
Bile duct cysts: cysts cause bile ducts to change and enlarge; also called Caroli disease.
Gallbladder conditions: ongoing gallbladder inflammation (cholecystitis); gallstones also raise risk.
Liver parasites (liver flukes): in areas of Southeast Asia; infection can happen from eating raw or undercooked fish.
Complications
Hilar cholangiocarcinoma can lead to several complications, mostly because the tumor blocks the flow of bile from the liver. This blockage can cause infections, liver damage, and other issues that affect digestion and overall health:
Cholangitis: infection in the bile ducts — when bile can't drain properly, bacteria grow inside the ducts, leading to infection, fever, and chills.
Liver damage and liver failure: long-term bile blockage scars and damages the liver, impairing its function.
Malnutrition and vitamin deficiency: bile helps digest fats; blockage causes poor absorption of nutrients and vitamins, leading to weight loss and weakness.
Portal hypertension: tumor growth or scarring increases pressure in the liver's veins, possibly causing abdominal swelling or enlarged veins in the esophagus.
Metastasis (cancer spread): the liver and nearby lymph nodes are common sites of spread; spread to distant sites such as the lungs, brain, and bones is not common.
How Is Hilar Cholangiocarcinoma Diagnosed?
Diagnosing hilar cholangiocarcinoma often begins with a physical exam and questions about your health history. You may have imaging tests and blood tests, and a sample of tissue may be taken for lab testing.
Imaging Tests
Imaging tests make pictures of the inside of the body. They help your healthcare team see the location, size, and spread of a hilar cholangiocarcinoma.
Ultrasound: often the first test; shows whether the bile ducts are blocked or enlarged.
CT scan: detailed pictures of the liver and bile ducts, especially the blood vessels going into the liver; helps show if the cancer has spread or can be removed with surgery.
MRI: even more detailed pictures of the liver and bile ducts.
MRCP (magnetic resonance cholangiopancreatography): a special MRI that makes clear images of the bile ducts, liver, gallbladder, and pancreas to find the exact spot of the blockage or tumor.
ERCP and PTC: when imaging shows a blockage, these procedures look at the bile ducts, obtain tissue samples, and define the extent of the tumor; they can also relieve the blockage by placing stents or drainage tubes to allow bile to flow — often improving symptoms and preventing infection.
Blood Tests
Liver function tests measure how well your liver is working and can give your healthcare team clues about what is causing your symptoms.
Tumor marker tests look for substances called tumor markers, which are often made by cancer cells or by healthy cells in response to cancer. Tumor markers for hilar cholangiocarcinoma include carbohydrate antigen 19-9 (CA 19-9) and carcinoembryonic antigen (CEA) — proteins overproduced by cholangiocarcinoma cells. High levels may point to a more advanced cancer, though high CA 19-9 and CEA levels can also happen with other bile duct conditions, such as bile duct inflammation and obstruction.
Biopsy
A biopsy removes a sample of tissue for testing in a lab. To get a tissue sample from a hilar cholangiocarcinoma, a healthcare professional might use ERCP. During this procedure, a thin tube with a camera (endoscope) is passed down the throat, through the stomach, and into the small intestine to reach the bile duct. Contrast material is injected into the bile duct so it shows more clearly on X-rays, and a brush tool extends from the endoscope to collect cells from the cancer.
Treatment Options
Treatment depends on the location and extent of the cancer. Surgery is the main treatment and offers the only chance to cure the disease if all the cancer can be taken out. For some people, a liver transplant may also be an option.
If surgery or transplant is not possible, other treatments are used to control the cancer and ease symptoms — including radiation therapy, radiofrequency ablation, and medicines (chemotherapy, targeted therapy, and immunotherapy). Your healthcare team considers your overall health, the type and stage of your cancer, and your preferences when creating a plan.
Surgery
The goal of surgery is to take out all of the cancer, but it may not be an option for everyone — the cancer grows near many important structures, which can make surgery difficult. Less than half of people can have surgery when they are first diagnosed, because many already have cancer that has spread too far.
Remove the cancer: often includes taking out and rebuilding part of the bile duct and nearby structures, such as surrounding ducts and parts of the liver and gallbladder.
Remove nearby lymph nodes: lymph nodes are tested for cancer; removing cancerous nodes may help prevent spread.
Liver transplant: if the cancer can't be removed with surgery but has not spread outside the liver, radiation therapy can be combined with a transplant — the surgeon removes the cancer and the entire liver, then places a healthy donor liver.
Biliary drainage: restores the flow of bile if cancer blocks a duct — a thin tube drains the bile, bypass surgery routes the duct around the cancer, or stents hold open a collapsing duct; relieves symptoms.
Radiation Therapy
Radiation therapy treats cancer with powerful energy beams — the energy can come from X-rays, protons, or other sources. During treatment, you lie on a table while a machine moves around you, directing radiation to precise points on your body.
For hilar cholangiocarcinoma, radiation is sometimes combined with chemotherapy to kill cancer cells that remain after surgery, or with chemotherapy to treat cancer that has spread to the lymph nodes.
Another procedure, radioembolization, places small beads that hold radiation into a blood vessel that leads to the cancer. The beads travel through the blood vessel and block the blood supply to the cancer while emitting radiation directly to it.
Chemotherapy
Chemotherapy treats cancer with strong medicines — most are given through a vein, and some come in pill form. It may be used after surgery to kill any remaining cancer cells. For advanced cancer that cannot be removed with surgery, chemotherapy may slow the growth of the cancer. It is sometimes combined with radiation therapy.
Targeted Therapy
Targeted therapy uses medicines that attack specific chemicals in cancer cells. By blocking these chemicals, targeted treatments can cause cancer cells to die. It may be an option for advanced hilar cholangiocarcinoma that cannot be removed with surgery. Some cancer cells might be tested to see whether targeted therapy is likely to work on the cancer.
Immunotherapy
Immunotherapy uses medicine that helps the body's immune system kill cancer cells. Cancer cells survive by hiding from the immune system; immunotherapy helps immune cells find and kill the cancer cells. It may be an option for advanced cancer that cannot be removed with surgery.
Palliative Care
Palliative care is a special type of healthcare that helps you feel better when you have a serious illness. A team of doctors, nurses, and other specially trained professionals works to ease pain and other symptoms and improve quality of life for you and your family. Palliative care can be used at the same time as strong cancer treatments such as surgery, chemotherapy, immunotherapy, targeted therapy, or radiation therapy. Used with other treatments, palliative care can help people with cancer feel better and live longer.
Coping and Support
With time, you will find ways to cope with the feelings that come after a cancer diagnosis. Three practical approaches help:
Learn enough about your cancer: ask your healthcare team about test results, treatment options, and, if you want, prognosis — learning more can build confidence in treatment decisions.
Keep friends and family close: close relationships provide practical support (such as home care during hospital stays) and emotional support when you feel overwhelmed.
Find someone to talk with: a friend, family member, counselor, medical social worker, clergy member, or cancer support group — ask your team about local support groups.
Bottom Line
Hilar cholangiocarcinoma is a rare but serious bile duct cancer that often announces itself only when it begins blocking bile flow — usually through jaundice, itching, dark urine, or clay-colored stools. Because surgery offers the only chance of cure and only a minority of people qualify at diagnosis, persistent symptoms deserve a timely evaluation rather than waiting. If you or a loved one is facing this diagnosis, a full discussion with a specialist team about surgery, transplant, drainage, and systemic therapy options — along with palliative care and emotional support — can meaningfully improve quality of life.
Your next step: If you notice persistent jaundice, itching, dark urine, clay-colored stools, unexplained weight loss, or stomach pain, make an appointment with your doctor. If you have been diagnosed, ask your care team about all treatment options — including surgery, transplant eligibility, and clinical support resources.
Explore more of our liver health guides: Hepatocellular Carcinoma — what it is, the 10 risk factors, and how treatment protects your liver.
Frequently Asked Questions
What is hilar cholangiocarcinoma?
Hilar cholangiocarcinoma — also called perihilar cholangiocarcinoma or a Klatskin tumor — is a type of bile duct cancer that starts where the right and left bile ducts leaving the liver join to form the common hepatic duct. Bile ducts are the slender tubes that carry bile, the digestive fluid, from the liver to the small intestine.
Is hilar cholangiocarcinoma the same as bile duct cancer?
Hilar cholangiocarcinoma is one type of bile duct cancer. Cholangiocarcinoma (the medical term for bile duct cancer) is classified by location into three types: intrahepatic (inside the liver), hilar (at the junction of the two liver ducts), and distal (near the small intestine and pancreas). Hilar is the most common type, but bile duct cancer overall is rare.
What are the symptoms of hilar cholangiocarcinoma?
It may not cause symptoms at first. When the tumor grows and blocks the bile ducts, symptoms include yellowing of the skin and whites of the eyes (jaundice), itching, dark urine, clay-colored stools, stomach pain, fatigue, and weight loss. Make an appointment with a doctor if you have any symptoms that worry you.
What causes hilar cholangiocarcinoma?
The cause of most cases is not clear, but the cancer is often linked to long-term inflammation or injury of the bile ducts. It develops when bile duct cells get DNA changes that make them grow and divide too quickly and keep living when typical cells would die, forming a tumor.
What are the risk factors?
Risk factors include primary sclerosing cholangitis, older age (most often over 50), inflammatory bowel disease, liver cirrhosis, bile duct cysts (Caroli disease), gallbladder conditions (chronic cholecystitis and gallstones), and liver fluke infection from eating raw or undercooked fish in parts of Southeast Asia.
Can hilar cholangiocarcinoma be cured?
Surgery is the main treatment and offers the only chance to cure the disease if all the cancer can be taken out. However, fewer than half of people can have surgery at diagnosis because many already have cancer that has spread too far. For some, radiation therapy combined with a liver transplant is an option if the cancer has not spread outside the liver.
What happens if surgery is not possible?
Other treatments are used to control the cancer and ease symptoms, including chemotherapy, radiation therapy, radioembolization, targeted therapy, immunotherapy, and biliary drainage (stents or bypass to restore bile flow). Palliative care can be used alongside these treatments to ease pain and improve quality of life.
What complications can it cause?
Because the tumor blocks bile flow, complications can include infection in the bile ducts (cholangitis) with fever and chills, liver damage or failure, malnutrition and vitamin deficiency, portal hypertension (pressure in the liver's veins), and spread of the cancer — most often to the liver and nearby lymph nodes.
References
This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. If you have a cancer diagnosis, discuss treatment decisions with a qualified oncology team. This article reflects medical guidance current as of January 20, 2026.
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