How is bile duct cancer staged?
Staging is the process of finding out how far a cancer has spread. The stage (extent) of bile duct cancer is one of the most important factors in selecting treatment options and estimating a patient's outlook for recovery and outlook (prognosis).
A staging system is a standardized way for members of the cancer care team to summarize the extent of a cancer's spread. The stage of a cancer is determined by the results of the physical exam, testing (such as imaging and other tests), and by the results of surgery if it has been done.
The American Joint Committee on Cancer (AJCC) TNM system
The major system used to describe the stages of bile duct cancer is the American Joint Committee on Cancer (AJCC) TNM system. There are actually 3 different staging systems for bile duct cancers, depending on where they start.
Intrahepatic bile duct cancers (those starting within the liver) are staged separately from extrahepatic bile duct cancers. Also, extrahepatic bile duct cancers are split into 2 groups: perihilar tumors and distal tumors. The TNM system for all bile duct cancers contains 3 key pieces of information:
- T describes whether the main tumor has invaded through the wall of the bile duct and whether it has invaded other nearby organs or tissues.
- N describes whether the cancer spread to nearby (regional) lymph nodes (bean-sized collections of immune system cells located throughout the body).
- M indicates whether the cancer has metastasized (spread) to other organs of the body. (The most common sites of bile duct cancer spread are the liver, peritoneum [the lining of the abdominal cavity], and the lungs.)
Numbers or letters appear after T, N, and M to provide more details about each of these factors:
- The numbers 0 through 4 indicate increasing severity.
- The letter X means "cannot be assessed" because the information is not available.
Resectable versus unresectable bile duct cancers
The TNM system divides bile duct cancers into several groups that help give doctors an idea about a person's prognosis (outlook). But for treatment purposes, doctors often use a simpler system based on whether these cancers are likely to be resectable (able to be completely removed by surgery) or unresectable. In general terms, most stage III and IV tumors are unresectable, but there may be exceptions. Resectability is based on the size and location of the tumor, how far it has spread, and whether or not a person is healthy enough to have surgery.
Last Medical Review: 06/14/2012
Last Revised: 06/28/2012