The TMN system for liver cancer
Several systems can be used to divide liver cancer into stages. Doctors in different parts of the world might use different systems. In the U.S., the most commonly used system to stage liver cancer is the TNM system from the American Joint Committee on Cancer. Be sure to ask your healthcare provider to explain the stage of your cancer in a way you can understand.
The first step in staging is to find the value for each part of the TMN system. Here's what the letters stand for:
Here is what the letters mean in the TNM system:
- T describes the size of the main (primary) tumor and how far it has spread inside the liver and nearby areas.
- N says whether the cancer has reached the nearby lymph nodes.
- M says whether the cancer has spread (metastasized) to other organs in the body, such as the lungs or bones.
Numbers or letters after T, N, and M provider more details about each of these factors. There are also 2 other values that can be assigned:
- X means the provider does not have enough information to assess the extent of the main tumor (TX), or if the lymph nodes can cancer cells in them (NX).
- O means no sign of cancer, such as no sign of the primary tumor in the liver (TO).
Once your doctor knows your T, N, and M status, he or she uses this information to assign the cancer an overall stage grouping. Stage groupings are determined by combining the T, N, and M values from the TNM system. These groupings give an overall description of your cancer.
A stage grouping can have a value of 1 to 4 and are written as Roman numerals, I, II, III, and IV. The higher the number, the more advanced the cancer. Letters and numbers can be used after the Roman numeral to give more details.