Staging
Understanding Cancer

Once cancer has been confirmed, doctors determine the severity and extent of the disease through a process called staging. This important step in diagnosis allows doctors to form an accurate picture of your condition to determine the best approach to treatment. Staging may be different for blood-related and other cancers, but solid tumor cancers follow the T/N/M method:

T: Tumor - Indicates the size of the primary tumor and whether it is contained or has spread to surrounding tissue. This is broken down further into numbers 1 through 4, indicating the size and local spread. Generally, a T1 means the tumor is small and appears to be self-contained. A T4 indicates a relatively large tumor with observed spread to surrounding tissue.

TX Primary tumor cannot be evaluated

T0 No evidence of primary tumor

Tis Tumor in situ indicates early cancer that has not spread to neighboring tissue

T1, T2, T3, T4 Size and/or extent of localized spread of the primary tumor

N: Node - Indicates the extent of lymph node involvement beyond the primary tumor site. It is possible to have a small tumor (T1) with lymph node involvement (N2 or N3), indicating a more serious condition.

NX Regional lymph nodes cannot be evaluated

N0 No cancer found in the lymph nodes

N1, N2, N3 Extent of regional lymph nodes involvement, N3 being highest number/farthest extent of spread

M: Metastasis - Indicates the extent of the cancer's spread to other parts of the body. Regardless of cancer appearing in other areas of the body, the cancer is still named according to its site of origination. Kidney cancer that has spread (metastasized) to the liver is still kidney cancer.

MX Distant metastasis cannot be evaluated

M0 Cancer has not spread to other parts of the body

M1 Cancer has spread to distant parts of the body

Doctors then combine the numbers to determine the stage for each type of cancer, which varies according to preset criteria for that particular cancer. Generally, the stages are described as follows:

Stage 0	Cancer in its earliest stages, remaining fully contained at its site of origin
Stage 1 Stage 2 Stage 3	Indicates the size and number of tumors, extent of the spread to lymph nodes and surrounding organs. Higher stages indicate greater severity of involvement beyond the original/primary site.
Stage 4	Indicates cancer has spread beyond the region of origin to other organs, i.e. breast cancer has spread to the liver.

To learn more about the staging process for each type of cancer, talk with your doctor. He or she will be able to provide an explanation and additional information specific to your cancer diagnosis. Additional information on staging and types of cancer is available in the cancer section of our Health Information library and on the National Cancer Institute Web site at www.cancer.gov or the American Cancer Society Web site at www.cancer.org.