Diagnosis

If your doctor suspects cholangiocarcinoma, he or she may have you undergo one or more of the following tests:

• Liver function tests. Blood tests to measure your liver function can give your doctor clues about what's causing your signs and symptoms.

• Tumor marker test. Checking the level of carbohydrate antigen (CA) 19-9 in your blood may give your doctor additional clues about your diagnosis. CA 19-9 is a protein that's overproduced by bile duct cancer cells.

  A high level of CA 19-9 in your blood doesn't mean you have bile duct cancer, though. This result can also occur in other bile duct diseases, such as bile duct inflammation and obstruction.

• A test to examine your bile duct with a small camera. During endoscopic retrograde cholangiopancreatography (ERCP), a thin, flexible tube equipped with a tiny camera is passed down your throat and through your digestive tract to your small intestine. The camera is used to examine the area where your bile ducts connect to your small intestine. Your doctor may also use this procedure to inject dye into the bile ducts to help them show up better on imaging tests.
• Imaging tests. Imaging tests can help your doctor see your internal organs and look for signs of cholangiocarcinoma. Techniques used to diagnose bile duct cancer include ultrasound, computerized tomography (CT) scans and magnetic resonance imaging (MRI) combined with magnetic resonance cholangiopancreatography (MRCP). MRCP is increasingly being used as a noninvasive alternative to ERCP. It offers 3D images without the need for a dye to enhance the images.

• A procedure to remove a sample of tissue for testing. A biopsy is a procedure to remove a small sample of tissue for examination under a microscope.

  If the suspicious area is located very near where the bile duct joins the small intestine, your doctor may obtain a biopsy sample during ERCP. If the suspicious area is within or near the liver, your doctor may obtain a tissue sample by inserting a long needle through your skin to the affected area (fine-needle aspiration). He or she may use an imaging test, such as an endoscopic ultrasound or CT scan, to guide the needle to the precise area.

  How your doctor collects a biopsy sample may influence which treatment options are available to you later. For example, if your bile duct cancer is biopsied by fine-needle aspiration, you will become ineligible for liver transplantation. Don't hesitate to ask about your doctor's experience with diagnosing cholangiocarcinoma. If you have any doubts, get a second opinion.

If your doctor confirms a diagnosis of cholangiocarcinoma, he or she tries to determine the extent (stage) of the cancer. Often this involves additional imaging tests. Your cancer's stage helps determine your prognosis and your treatment options.