Colorectal cancer is the second leading cause of cancer-related deaths in the United States . The American Cancer Society estimates that about 145,000 cases of colorectal cancer will be diagnosed and about 56,000 people will die from the disease in 2005. In the U.K. , approximately 20,000 people die from colorectal cancer each year.

Colorectal cancer is the fourth commonest form of cancer occurring worldwide, affecting men and women almost equally. The number of new cases of colorectal cancer worldwide is increasing rapidly with an estimated 500,000 new cases diagnosed in 1975, 783,000 new cases diagnosed in 1990, and approximately 940,000 new cases in 2000.

Most (over 95%) colorectal cancers are adenocarcinomas which develop when a change occurs in cells that line the wall of the colon or rectum. The disease often begins as an intestinal polyp, which is by then only an abnormal growth of tissue. Polyps gradually can become precancerous and finally cancerous.

Colon Cancer is both highly preventable and treatable. More than 90% of colon cancer deaths can be prevented if pre-cancerous polyps are removed in time. This is why testing for any colorectal anomalies is so important.