Staging colon and rectal cancer

After undergoing many tests, you have finally been given your diagnosis. What does it mean when your doctor says you have stage I colon cancer or stage III rectal cancer? The following information will help you understand your diagnosis.

Stages of bowel cancer

Colon and rectal cancer are staged according to how far they have spread through the walls of the colon and rectum and whether they have spread to other parts of the body. This staging process allows doctors to determine the best treatments for the particular cancer. It also allows them to determine if the cancer is getting better with treatment or not responding.

Staging colon cancer

• Stage 0
  Stage 0 cancer of the colon is very early cancer. The cancer is found only in the innermost lining of the colon.
• Stage I
  Also called Dukes A colon cancer, the cancer has spread beyond the innermost lining of the colon to the second and third layers and involves the inside wall of the colon. The cancer has not spread to the outer wall of the colon or outside the colon.
• Stage II
  Also called Dukes B colon cancer, the tumour extends through the muscular wall of the colon, but there is no cancer in the lymph nodes (small structures found throughout the body that produce and store cells that fight infection).
• Stage III
  Also called Dukes C colon cancer, the cancer has spread outside the colon to one or more lymph nodes.
• Stage IV
  Also called Dukes D colon cancer, the cancer has spread outside the colon to other parts of the body, such as the liver or the lungs. The tumour can be any size and may or may not include affected lymph nodes.

Staging rectal cancer

Rectal cancer is staged much the same way as colon cancer, but because the tumour is much lower down in the colon the treatment options may vary.

• Stage 0
  In stage 0 rectal cancer, the tumour is only on the inner lining of the rectum. To treat this early stage cancer, surgery can be performed to remove the tumour, or a small section of the rectum where the cancer is located can be removed.
• Stage I
  Also called Dukes A rectal cancer, this is another early form, or limited form, of cancer. The tumour has broken through the inner lining of the rectum but has not made it past the muscular wall.
• Stage II
  Also called Dukes B rectal cancer, this cancer is a little more advanced. The tumour has penetrated all the way through the bowel wall and may have invaded other local organs, such as the bladder, uterus, or prostate gland.
• Stage III
  Also called Dukes C rectal cancer, the tumour has spread to the lymph nodes (small structures found throughout the body that produce and store cells that fight infection).
• Stage IV
  Sometimes called Dukes D rectal cancer, the tumour has spread to distant parts of the body (metastasised). The tumour can be any size and sometimes is not that large. The liver and lungs are two common organs of the body where rectal cancer spreads.