Stages of Colorectal Cancer

Colorectal cancer is cancer that affects the colon and the rectum. The National Cancer Institute estimates that over 100,000 new cases of colon cancer and 40,000 cases of rectal cancer are diagnosed each year. Nearly 50,000 Americans die from colorectal cancer annually. In order to understand the severity of colorectal cancer, physicians use the staging process. Colorectal cancer is broken into five stages.

Stage 0

• Stage 0 colorectal cancer is considered a pre-cancerous stage and is also known as carcinoma in situ. While cancer is not present, abnormal cells which could lead to cancer have been identified in the lining of the colon or rectum. If these cells become cancerous, they may spread from the colon or rectum to other parts of the body. At this stage, surgical removal of the cancer is the only treatment that is required.

Stage 1

• In stage 1 colorectal cancer, cancer has been found in the colon or rectum and extends beyond the inner lining of the colon or rectum into the middle layers. Cancer is not found outside of the colon or rectum.

  At this stage, colon cancer is usually removed through a resection. During a colon resection, the cancerous parts of the colon are removed and the two healthy ends of the colon surrounding the diseased tissue are joined together.

  To treat stage 1 rectal cancer, surgeons may choose to use a variety of surgical options dependent upon the location of the cancer. Typically, a surgeon will perform abdominoperineal resection, which removes the rectum, colon and anus. Chemotherapy and radiation may also be used to ensure the destruction of the cancer.

Stage 2

• Stage 2 colon cancer has moved beyond the middle layers and outer wall of the colon to the surrounding tissue, but has not affected the lymph nodes. A colon resection is the only surgical option available at this stage and may also be accompanied by chemotherapy and radiation in order to prevent recurrence of the cancer.

  Stage 2 rectal cancer means that the cancer has moved beyond the walls of the rectum into the surrounding tissue but has not damaged the lymph nodes. Stage 2 rectal cancer is treated with an abdominoperineal resection as well as chemotherapy and radiation.

Stage 3

• By stage 3 colorectal cancer, the cancer is considered to be advanced. At this point, cancer reaches beyond the colon or rectum to the lymph nodes. However, it has not affected any other tissue or organs. Resection is required for both types of cancer along with chemotherapy and radiation.

Stage 4

• By stage 4 colorectal cancer, the cancer has spread to other body organs and tissue. Surgery is still performed at this stage, but is done as a means to eliminate pain versus destroying the cancer. Depending on the location of the cancer, it may be possible to remove all of it, but this is generally not the case in stage 4 colorectal cancer. Chemotherapy and radiation are usually administered at this stage as well.