Intrahepatic Cholangiocarcinoma (Bile Duct Cancer)

Bile is a greenish-golden yellow liquid produced by the liver for digestion of fat in the intestine. This bile is then carried from the liver to intestine by the bile duct. The bile duct is a tree-like network of tubules. It starts in the liver as smaller tubes (intrahepatic ducts) and progressively combines to form larger tubules. The branches of the right and left side of the liver coalesce to form right and left hepatic duct.

The right and left hepatic duct then join (the joint called hilum or confluence) and continues further as a single tube called common bile duct. The common bile duct goes out of the liver (extrahepatic bile duct) and joins the intestine (in the duodenum) after passing through the head of the pancreas.

The average age at which patients are diagnosed with intrahepatic cholangiocarcinoma is 70 years.

When cancer affects the joint of the left and right duct, it is called perihilar or hilar cholangiocarcinoma. While cancer affecting the part of the duct where it joins the intestine is known as distal bile duct cancer.

Blood tests

Includes routine blood tests, blood clotting parameters and liver function tests.

Tumour markers

These are substances which are elevated in the blood of patients suffering from cancers. In intrahepatic cholangiocarcinoma, CA19.9 and carcinoembryonic antigen (CEA) may be elevated.

Computed tomographic (CT) scan

This modality uses x-ray beams and computer processing to see inside. Thin cut liver protocol triple-phase CT is done to visualise cancer and the involved parts of the liver, bile ducts and adjacent vessels. It also gives information about the distant spread of the disease.

Magnetic resonance imaging

MRI uses strong magnetic fields, radio waves and computer to generate images of inside organs. This imaging modality also gives structural information about cancer, liver, bile duct and adjacent vessels.

Positron emission tomography (PET) scan

It is a functional imaging technique which is sometimes used for staging. This helps differentiate cholangiocarcinoma from tumours which have spread to the liver from other organs.

Biopsy or cytology

In this procedure, a small sample of tumour or few cells from it is obtained and examined under the microscope confirming the diagnosis. Patients may require a biopsy if the diagnosis is in doubt, or the surgery is not planned.

Upper GI endoscopy and colonoscopy

With this thin flexible tube with a camera is passed in upper and lower parts of the intestine and they are seen from inside. This is done to make sure that the tumour in the liver has not spread from any cancer in the oesophagus, stomach or colon.

Once diagnosed, the cancer is staged. Staging tells us about the current state of the tumour, its size, its location and how much it has spread to adjacent areas and to organs which are away from the site of origin. Staging helps the oncologists and surgeons formulate a treatment plan.

TNM (tumour, node and metastasis) classification

Developed by the American Joint Committee on Cancer (AJCC) is used for exact classification of stage and it spans from I to IV.

Surgical resection is the treatment of choice for intrahepatic bile duct cancer. The surgery for removal of intrahepatic cholangiocarcinoma requires removal of the bile duct and the part of the liver it is affecting. The surgical procedure to remove a part of the liver is called hepatectomy or liver resection. The joint of the left and right duct also needs excision in many cases. The bile is then made to reach intestine by joining a loop of intestine to the cut end of the bile duct of remnant liver.

Whether the tumour is amenable to surgery by partial removal of the liver depends on many factors including how much liver needs to be removed, how healthy the liver is, whether blood supply and drainage of remaining liver can be preserved and whether the amount of remaining liver is adequate (functional liver remnant � FLR).

Surgical excision is done only for those patients whose tumours have not spread to distant organs. Besides complete resection should be feasible with sufficient FLR.

Sometimes the amount of liver which needs to be removed is too big and hence the remaining liver is small and not compatible with survival. In such cases, portal vein embolization can be done a few weeks before the surgery to increase the size of the liver, which is going to remain after surgery.

If the jaundice is very high, then it needs to be brought down before the surgery by a procedure called percutaneous transhepatic biliary drainage (PTBD) or Endoscopic retrograde cholangiopancreatography (ERCP). In these procedures drainage tube is placed in the blocked bile duct, draining the bile and decreasing jaundice.

For tumours which are unresectable or have spread to distant organs, the palliative treatment is given. It aims at prolonging life and improving the quality of life. The option for such patients includes chemotherapy, radiotherapy and liver-directed therapy.

In chemotherapy drugs are given which kills the cancer cells temporarily. Radiotherapy is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumours. Liver-directed therapy can include treatment with radioembolization with yttrium-90 (Y-90), transarterial chemoembolization, and ablation, most commonly radiofrequency ablation.