Bile duct cancer (cholangiocarcinoma)

Bile duct cancer is almost always a type of cancer called adenocarcinoma, which starts in the lining of the bile duct. If cancer starts in the part of the bile ducts within the liver, it is known as intra-hepatic. If it starts in bile ducts outside the liver, it is known as extra-hepatic.

The bile ducts :

The bile ducts are tubes that carry bile. The main function of bile is to break down fats in food to help our digestion. Bile is made by the liver and stored in the gall bladder. The bile ducts connect the liver and gall bladder to the small bowel (see diagram below). When people have had their gall bladder removed, bile flows directly from the liver into the small intestine. The bile ducts and gall bladder are known as the biliary system.

Etiology (causes of bileduct cancer)

The cause of most bile duct cancers is unknown. There are a number of risk factors that can increase your risk of developing bile duct cancer. These include:

• Inflammatory conditions : People who have a chronic inflammatory bowel condition, known as ulcerative colitis, have an increased risk of developing this type of cancer.
  
• Abnormal bile ducts: People who are born with (congenital) abnormalities of the bile ducts, such as choledochal cysts, have a higher risk of developing bile duct cancer.
  
• Infection: In Africa and Asia, a large number of bile duct cancers are thought to be caused by infection with a parasite known as the liver fluke.
  
• Increasing age: Although bile duct cancers can occur in younger people, more than two out of three occur in people over 65.

The Cow Belt (Up.Bihar) has one of highest incidence of gall bladder cancer in the world.

Signs and symptoms of bile duct cancer

• Cancer in the bile ducts can block the flow of bile from the liver to the intestine. This causes bile to flow back into the blood and body tissues, and the skin and whites of the eyes to become yellow (jaundice). It also causes the urine to become a dark yellow colour and stools (bowel motions) to look pale. The skin may become itchy.
  
• Other possible symptoms include discomfort in the tummy area (abdomen), loss of appetite, high temperatures (fevers) and weight loss.
  

These symptoms can be caused by many things other than bile duct cancer, but it's important to get them checked by your doctor.

How is bile duct cancer diagnosed?

Usually you begin by seeing your local physician, who will examine you. They will refer you to a hospital specialist for any necessary tests, expert advice and treatment.

At the hospital, the doctor will ask you about your general health and any previous medical problems. They will also examine you and take blood samples to check your general health and that your liver is working properly.

The following tests are commonly used to diagnose bile duct cancer:

• ULTRASOUND
  
• CT (computerised tomography) scan
  
• MRI (magnetic resonance imaging) scan
  
• ERCP (endoscopic retrograde cholangio-pancreatography)
  
• Endoscopic ultrasound scan (EUS)
  
• Biopsy
  

• Stage 1A: The cancer is contained within the bile duct.
  
• Stage 1B: The cancer has spread through the wall of the bile duct but hasn't spread into nearby lymph nodes or other structures.
  
• Stage 2A: The cancer has spread into the liver, pancreas, gall bladder or nearby blood vessels, but not the lymph nodes.
  
• Stage 2B: The cancer has spread into nearby lymph nodes.
  
• Stage 3: The cancer is affecting the main blood vessels that take blood to and from the liver, or it has spread into the small or large bowel, the stomach or the abdominal wall. Lymph nodes in the abdomen may also be affected.
  
• Stage 4: The cancer has spread to distant parts of the body such as the lungs.
  

If the cancer comes back after treatment, it is known as recurrent cancer.

Treatment

The treatment you have will depend on the position and size of the cancer, whether it has spread beyond the bile duct and your general health. In some situations, the aim of treatment will be to relieve symptoms.

• Surgery: The main treatment for bile duct cancer is surgery to remove the cancer. But this may involve a major operation and isn't always possible. The decision about whether surgery is possible and the type of operation that may be done depends on the size of the cancer and whether it has begun to spread into nearby tissues.
  
  If surgery is recommended, you will be referred to a surgeon who is a specialist in this rare cancer.

• Removal of the bile ducts: If the cancer is at a very early stage (stage 1), only the bile ducts containing the cancer are removed. The remaining ducts in the liver are then joined to the small bowel, allowing the bile to flow again.
  
  
• Partial liver resection: If the cancer has begun to spread into the liver, the affected part of the liver and the bile ducts are removed.
  
  
• Whipple's procedure: If the cancer is larger and has spread into nearby structures, then the bile ducts, part of the stomach, part of the small bowel (duodenum), the pancreas, gall bladder and the surrounding lymph nodes are all removed.
  
  
• Surgery to relieve blockage (obstruction): If it isn't possible to remove the tumour, you may have an operation to relieve the blockage. This will also help to relieve jaundice.
  
  The surgeon operates to create a bypass of the blocked part of the bile duct, so the bile can flow from the liver into the intestine. Another method of relieving a blockage, without an operation, is to insert a tube (stent) into the duct holding it open.
  
  If a part of the small bowel called the duodenum is blocked, it can cause sickness (vomiting). This may be helped with an operation where the surgeon connects the stomach to the next section of small bowel (the jejunum), bypassing the duodenum.
  
  
• Stent insertion: A stent is a tube put into the bile duct to hold it open and allow bile to drain away. The tube is about as thick as a ballpoint pen refill and about 5-10cm (2-4in) long. A stent may be put in using an ERCP or occasionally a PTC procedure.
  
  A stent usually needs to be replaced every 3-4 months to prevent it from becoming blocked. If the stent becomes blocked you may have high temperatures and/or jaundice. It's important to tell your specialist as soon as possible if you develop these symptoms. You may need antibiotic treatment and your specialist may advise that the stent be replaced. This is usually done quite easily.
  
  
• Radiotherapy: Radiotherapy treats cancer by using high-energy rays to destroy cancer cells, while doing as little harm as possible to normal cells. It may be given externally from a radiotherapy machine, or internally by placing radioactive material close to the tumour (brachytherapy).
  
  Radiotherapy may occasionally be used after surgery for bile duct cancer. This is called adjuvant radiotherapy and is given to try to reduce the risk of cancer coming back.
  
  Radiotherapy is also sometimes used if an operation isn't possible. It can't cure the cancer but it may help shrink it or slow its growth.
  
  
• Chemotherapy: Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. They work by disrupting the growth of cancer cells.
  
  Chemotherapy may occasionally be used after surgery if all the cancer couldn't be removed by the operation. It may also be used if an operation isn't possible or the cancer has come back (recurred) after initial treatment. The aim of chemotherapy treatment is to try to shrink or slow down the growth of the cancer and to relieve symptoms. A combination of the drugs cisplatin and gemcitabine (Gemzar®) can be used to treat bile duct cancer.