Colorectal Cancer Health Center

Staging Colon and Rectal Cancer

After undergoing many tests, you have finally been given your diagnosis. But, 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 better.

Colorectal Cancer: See How It Starts and How It Is Treated

Stages of Colorectal 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.

Learn more about treatments for stage 0 colon cancer.

Stage I
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.

Learn more about treatments for stage I colon cancer.

Stage II
 The tumor extends through the muscular wall of the colon, but there is no cancer in the lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection).

Learn more about treatments for stage II colon cancer.

Stage III
The cancer has spread outside the colon to one or more lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection).

Learn more about treatments for stage III colon cancer.

Stage IV
The cancer has spread outside the colon to other parts of the body, such as the liver or the lungs. The tumor can be any size and may or may not include affected lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection).

Learn more about treatments for stage IV colon cancer.

Staging Rectal Cancer

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

Stage 0
In stage 0 rectal cancer, the tumor is located only on the inner lining of the rectum. To treat this early stage cancer, surgery can be performed to remove the tumor or a small section of the rectum where the cancer is located can be removed.

Learn more about treatments for stage 0 rectal cancer.

Stage I

This is an early form or limited form of cancer. The tumor has broken through the inner lining of the rectum but has not made it past the muscular wall.