Grading and Staging of Colorectal Tumors

Abnormal cells in the lining of the colon.

When colorectal cancer is discovered in the early stages, chance of a cure is nearly 90 percent. Sometimes staging is not complete until after surgery to remove the tumor.

  • Stage 0 or Carcinoma in situ:¬†Cancer is found only in the innermost and most superficial lining of the colon or rectum.
  • Stage I: Cancer cells have grown into the inner wall of the colon or rectum, but not through the wall.
  • Stage II: The tumor extends more deeply into or through the wall of the colon or rectum. It may have invaded nearby tissue, but cancer cells have not spread to the lymph nodes.
  • Stage III: Cancer has spread to nearby lymph nodes, but not to other parts of the body.
  • Stage IV: Cancer has spread to other parts of the body, such as the liver or lungs.
  • Recurrence: Cancer that has been treated and has returned after a period of time when it could not be detected. The disease may return in the colon or the rectum, or in another part of the body.