More staging details
This material and image is available on the American Cancer Society website and is adapted from that site.
T categories for colorectal cancer
T categories of colorectal cancer describe the extent of spread through the layers that form the wall of the colon and rectum. These layers, from the inner to the outer, include:
- the inner lining (mucosa)
- a thin muscle layer (muscularis mucosa)
- the fibrous tissue beneath this muscle layer (submucosa)
- a thick muscle layer (muscularis propria) that contracts to force the contents of the intestines along
- the thin, outermost layers of connective tissue (subserosa and serosa) that cover most of the colon but not the rectum
- Tx: No description of the tumor’s extent is possible because of incomplete information.
- Tis: The cancer is in the earliest stage. It involves only the mucosa. It has not grown beyond the muscularis mucosa (inner muscle layer).
- T1: The cancer has grown through the muscularis mucosa and extends into the submucosa.
- T2: The cancer has grown through the submucosa and extends into the muscularis propria (outer muscle layer).
- T3: The cancer has grown through the muscularis propria and into the subserosa but not to any neighboring organs or tissues.
- T4: The cancer has grown through the wall of the colon or rectum and into nearby tissues or organs.
N categories for colorectal cancer
N categories indicate whether or not the cancer has spread to nearby lymph nodes and, if so, how many lymph nodes are involved.
- Nx: No description of lymph node involvement is possible because of incomplete information.
- N0: No lymph node involvement is found.
- N1: Cancer cells found in 1 to 3 nearby lymph nodes.
- N2: Cancer cells found in 4 or more nearby lymph nodes.
M categories for colorectal cancer
M categories indicate whether or not the cancer has spread to distant organs, such as the liver, lungs, or distant lymph nodes.
Mx: No description of distant spread is possible because of incomplete information.
M0: There is no evidence of distant spread.
M1: Cancer has been found in a distant organ.
There are other staging systems that are sometimes used to describe how far colon or rectal cancer has spread. Don’t be confused if your doctor uses letters like A, B, C, or D.
If your stage is reported in letters rather than numbers, your doctor is likely referring to one of the other staging systems sometimes used for colorectal cancer either the Dukes or Modified Astler-Coller.
Where Can You Go for More Information?
National Cancer Institute Dukes Staging.
Last Update: April 8, 2008
Medical Review
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