​The liver is largest solid organ in the body and is essential for life. It is involved in many processes of the body, such as producing bile, essential proteins, nutrients and detoxification among others. Bile ducts within the liver join together to form one main bile duct, located just outside the liver (at the hilum), which carries bile to the small intestine. This main bile duct is called the common hepatic duct. The cystic duct joins the gallbladder to the common hepatic duct, and the combined duct is called the common bile duct. (Figure 1)

Cholangiocarcinoma (CCA) (bile duct cancer) is next most common primary cancer of the liver, after hepatocellular carcinoma (HCC). It arises from cells lining the bile ducts (cholangiocytes).  

They can occur within the liver (intrahepatic) or near the liver hilum (perihilar) or beyond the liver (extrahepatic or distal).  Tumours involving the bile duct bifurcation (hilar) are also known as "Klatskin" tumours. Although they are rare, these cancers are highly lethal because most are locally advanced at presentation.

​Extrahepatic CCAs usually become symptomatic when the tumour obstructs the bile duct drainage system. Symptoms related to biliary obstruction include yellowing of skin and eye (jaundice), itchy skin (pruritus), clay-coloured stools and tea-coloured urine. Other common symptoms include abdominal pain, weight loss, fever and chills. The pain is generally described as a constant dull ache in the right upper abdomen.  Malaise, fatigue, and night sweats may be present at times.

Intrahepatic CCAs may present differently as the tumour is in the liver. Affected patients are less likely to be jaundiced. They may have a history of dull right upper quadrant pain, weight loss, and an abnormal liver test (e.g. elevated alkaline phosphatase)

Some patients will have mild or no symptoms. It may be detected by chance as a result of an scan for other problems. Occasionally, there may be vague symptoms of heaviness or discomfort in the right side of the abdomen. Pain and poor appetite or weight loss or fatigue are usually late symptoms.

Other uncommon presentations include abdominal distension due to fluid accumulation (ascites) or breathlessness due to the cancer spreading (metastasis) to the other parts of the body e.g. bone and internal lining of the abdomen(peritoneum).

​There are no known ways to prevent most bile duct cancers. Many of the known risk factors for bile duct cancer, such as age, ethnicity, genetics and bile duct abnormalities are beyond our control. Nonetheless, there are some things you can do that might lower your risk.

You can lower your risk for developing CCA by leading a healthy lifestyle, such as regular exercise, controlling your weight, and eating a healthy balanced diet.

It's also important to avoid infection with the hepatitis B and C viruses. Hepatitis B and/or C infection may increase the risk of developing CCA and it can lead to liver scarring (cirrhosis), liver failure and liver primary cancer.  There is no vaccine for hepatitis C currently but the right treatment may control or eliminate the virus. If you have chronic hepatitis, you should visit your doctors for regular surveillance with imaging tests, such as ultrasound.

Quit (or don't start) smoking and avoid excessive alcohol consumption.

Avoid exposure to known cancer-causing (carcinogenic) chemicals

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Any cause of chronic inflammation and/or infection to the bile ducts can increase the risk of developing CCA due to long-standing repeat damage, these include bile duct stones or parasites. (e.g. liver flukes, recurrent pyogenic cholangitis)

These are some other inflammatory conditions can increase the risk of developing CCA.

• Ulcerative Colitis – This is chronic inflammation of the large intestine that is often associated with inflammation of the bile duct (a condition known as sclerosing cholangitis). Patients with primary sclerosing cholangitis (PSC) are at an elevated risk for CCA.
• Congenital Bile Duct Cysts (Choledochal Cysts) - These are abnormal dilated bile ducts, they are usually congenital in nature and are typically diagnosed in childhood but may develop or be detected in adulthood. The lining of these sacs often contains pre-cancerous cells that increase the risk of developing cancer later in life.
• Parasite infestation - Liver fluke infections are not uncommon especially in Asia, it occurs when people eat raw or poorly cooked fish that are infected with these tiny parasite worms. In humans, these flukes live in the bile ducts and can cause bile duct cancer. The types most closely related to CCA are Clonorchis sinensis, Schistosomiasis japonica and Opisthorchis viverrini
• Chronic Hepatitis C infection – This is a risk factor for intrahepatic CCA.
• Exposure to cancer-causing (carcinogenic) agents such as Asbestos, Thorotrast, dioxins, nitrosamines, and vinyl chloride has been linked causing CCA.
• Smoking – Studies suggests that intrahepatic CCA is more common among heavy smokers.
• Diabetes and Obesity - These metabolic conditions appear to be an increasingly associated risk factors for intrahepatic CCA.

​The disease is notoriously challenging to diagnose early, and is usually advanced because of its late presentation and the lack of effective non-surgical therapeutic modalities

It is important to get an accurate diagnosis of CCA so that your condition can be treated appropriately. Your doctor will ask questions about your medical and family history, lifestyle habits and perform a physical examination.

The simplest imaging study of the liver is an ultrasound. There is no radiation risk and can be done on a regular basis, especially in individuals who are at risk of cancer, for e.g. hepatitis C carriers. It is however not always accurate and or very specific.

A CT scan is a better way of detecting CCA and is crucial for treatment planning. This would be the basic imaging that will be done to detect and plan a treatment strategy. In certain cases, a CT scan may not be enough or is inconclusive, and additional investigations like MRI/ MRCP or a PET scan may be performed.

A blood test that measures the level of a tumour markers called Carbohydrate antigen 19–9 (CA 19-9) is associated with CCA but it should not be used in isolation or as a routine screening test. Other tumour markers that are associated are carcinoembryonic antigen (CEA) and CA-125.

A small amount of bile duct tissue or cells may be sampled via a needle procedure (liver biopsy) or via endoscopy brushing, this may be required to guide management and/or if the diagnosis is unclear.

Other scans or investigations may be required if necessary for diagnosis, staging and/or to guide treatment strategy.

​After the bile duct cancer is found and staged, your specialist team will discuss your treatment options with you. In choosing a treatment plan, these are some factors to consider:

• The location and extent of the cancer
• Whether the cancer is resectable (removable by surgery)
• The likely side effects of surgery and other alternative treatment
• Your overall health and fitness for surgery
• The chances of curing the disease, extending life, or relieving symptoms

The main types of treatment for bile duct cancer include:

• Surgery
• Radiation therapy
• Chemotherapy
• Palliative therapy
• Combination of various treatment options may be offered as well to optimise the treatment results

Surgery is often the best treatment for CCA when it is at an early stage and hasn't spread to nearby blood vessels or distant organs. Other methods have not been shown to be as effective as surgery in treating CCA.  However, due to its advanced stage at first presentation, surgery may not be possible for some patients.

As surgery is the only effective method for treating CCA, it is important that a person with suspected CCA has a proper assessment by a specialist team lead by a liver surgeon is known as a Hepato-Pancreato-Biliary (HPB) surgeon. Surgery is currently safe and effective in treating CCA if amenable.

Depending on the location of the cancer, surgery for CCA includes cutting out the tumour (Liver resection) or Enbloc removal of the bile duct and its surrounding organs and lymph nodes. (E.g. Pancreaticoduodenectomy or also known as a "Whipple" procedure ; or Radical bile duct resection).

Liver transplant – A small selected group of Intrahepatic CCA patients may be suitable for a liver transplantation.

Clinical trials test new drugs, surgical techniques and strategies for advancing treatment and care. There may be suitable clinical trials available for selected patients. Please consult your specialist for advice.

​Your surgeon will perform a comprehensive work-up including blood tests, scans to see if you are suitable for surgery and advise you on the risks involved. This treatment recommendation is often based on consensus by a group of different specialists' opinions (tumour board) which weighs the pros and cons of every treatment strategy.

Before surgery, the anaesthesia team will also assess your fitness for surgery and advise you on various aspects of general anaesthesia aspects and pain control after surgery.

Specialist nurses will also available for pre- surgery counselling.

​After recovering from your surgery, you will be given regular outpatient appointments to see your team of doctors and these will include blood test and scans to check if the cancer recurs.

It is important to follow all your doctor's advice, clinic visits and tests so that timely treatment can occur if the cancer or other problems arises.