Colorectal cancer is the growth of abnormal cells in the colon or rectum. Normally, cells divide and form new cells when the body needs them. This process helps keep the body healthy. If, instead, cells divide when new cells are not needed, a mass of tissue, or growth, forms. This mass of tissue or growth is sometimes called a tumor.
Colorectal cancer can start with noncancerous growths called polyps .
The spread of cancer is called metastasis . Reducing the number of deaths from colorectal cancer depends on detecting and removing precancerous polyps, as well as on detecting and treating this cancer in its early stages. The colon and rectum make up the lowest section of the digestive tract. The colon is also called the large bowel or large intestine. It is the last five to six feet of intestine.