Cancer stages

Staging is an essential step to determine if a cancer has spread and how it will be treated. Not all cancers are staged the same way. The American Joint Committee on Cancer and International Union for Cancer Control maintain and update the TNM classification system every six to eight years. It is the most common staging system.

T = the original tumor

N = cancer has spread to nearby lymph nodes M = cancer has spread to other parts of the body

Roman numerals after the T, N and M indicate how advanced the cancer is. For most cancers, the lower the number, the less invasive the cancer. The prognosis is usually not as good for higher stages.

0: Cancer is at a very early stage and may never progress.

I: Cancer is found only where it started (localized).

II: Cancer has spread to nearby tissue but not lymph nodes.

III: Cancer cells are in nearby lymph nodes and may be in the

bloodstream.

IV: Metastatic cancer has spread to the bloodstream and distant organs.