Staging Anal Cancer

Anal cancer staging refers to the size of the tumor, and whether cancer cells have spread to other body locations. Anal cancers fall into one of these six stages:

  • Stage 0 (Carcinoma in Situ): Abnormal cells are found in the innermost lining of the anus.
  • Stage I: The cancer has formed into a tumor which is 2 centimeters (cm), the size of a peanut M&M or smaller.
  • Stage II: The tumor is larger than 2 cm.
  • Stage III: The tumor is any size and has spread to:
    • lymph nodes near the rectum, or
    • nearby organs (urethra, bladder or vagina)
  • Stage IIIB: The tumor is any size and has spread to:
    • lymph nodes near the rectum and nearby organs (urethra, bladder or vagina); or
    • lymph nodes on one side of the pelvis/groin, and may have spread to nearby organs; or
    • lymph nodes near the rectum and the groin, and/or to lymph nodes on both sides of the pelvis/groin, and may have spread to nearby organs
  • Stage IV: The tumor is any size, and may have spread to lymph nodes or nearby organs, and has spread to distant body sites.

Recurrent anal cancer: Anal cancer that has recurred after having been treated with chemoradiation.