Bile Duct Cancer Tests
How Is Bile Duct Cancer Detected?
The bile ducts are located deep within the body, making it difficult to detect early tumors during a standard physical. Additionally, there are no reliable screening options for bile duct cancer, so it tends to be diagnosed at later stages when the cancer has grown and spread.
How Is Bile Duct Cancer Diagnosed?
To diagnose bile duct cancer, doctors first assess your personal and family health histories, in addition to your risk factors and symptoms. You must also undergo a physical exam and one or more of the following tests:
To conduct a biopsy, a small piece of the bile duct is removed and analyzed by a pathologist to determine if there is cancer present.
Liver function tests can identify bile duct blockages, as can liver enzyme tests. Liver enzyme tests are also used to recognize inflammation and irritation of the liver.
Additional blood tests may be conducted to detect elevated levels of certain substances known as tumor markers.
Abdominal ultrasound: The initial imaging test a patient undergoes is usually an ultrasound. This type of test uses sound waves to create images of potential bile duct cancer tumors. Abdominal ultrasounds require no radiation and are noninvasive.
A doctor or ultrasound technician simply moves a wand-like instrument over your abdomen to capture the echoes that bounce off your internal organs. Those echoes are converted into images with the help of specialized computer programs.
Endoscopic or laparoscopic ultrasound: These ultrasounds provide more detailed images, as they allow for closer access to the bile duct area. Endoscopic and laparoscopic ultrasounds may be used to assist in removing tissue for a biopsy and determining if cancer has spread. During these procedures, a thin tube fitted with a light at the end is inserted through the mouth and down the throat, or through a small incision in the side of the body.
Endoscopic retrograde cholangiopancreatography (ERCP): During this procedure, an endoscope is inserted down the throat, followed by a smaller scope that dispenses dye into the bile ducts. X-rays can then pick up on the dye and reveal any visible abnormalities. If necessary, doctors can also insert stents to unblock bile ducts during an ERCP.
Magnetic resonance cholangiopancreatography: Similar to a MRI, this test takes thorough pictures of the bile ducts. Unlike the ERCP, it is noninvasive and does not use radiation.
Percutaneous transhepatic cholangiography: Useful in detecting bile duct cancer located inside the liver, this is a more invasive but more accurate procedure. For this test, doctors use a needle to inject dye into the bile ducts. X-rays can then detect any existing problems or blockages. PTC may show the exact location and size of bile duct cancer tumors, and determine if they can be removed surgically.
How Is Bile Duct Cancer Staged?
Accurate staging is crucial for developing the best possible cancer treatment plan. To begin, the type of bile duct cancer is classified based on its location.
Intrahepatic bile duct cancer starts inside the liver, perihilar (or hilar) bile duct cancer start just outside the liver and distal bile duct cancer starts near the small intestine.
Next, doctors determine the cancer’s severity by evaluating the size of the primary tumor and whether it has grown through the wall of the bile duct, if the cancer has reached nearby lymph nodes and if it has spread to other parts the body.