Colorectal Cancer

Stages of Colorectal Cancer

After colorectal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the colon or to other parts of the body. This is called staging. CT or MRI scans of the abdomen, pelvic area, chest, or brain may be used to determine the stage of the cancer. In some cases, positron emission tomography, or PET scans, may also be used.

The stages of colon cancer are:

  • Stage 0: Very early, localized cancer on the innermost layer of the colon
  • Stage I: Cancer is in the inner layers of the colon
  • Stage II: Cancer has spread through the muscle wall of the colon
  • Stage III: Cancer has spread to the lymph nodes
  • Stage IV: Cancer has spread to other organs