Evidence Points to Colonoscopy in Preventing Colorectal Cancer

Colorectal Cancer, also known as Colon Cancer, is the third most common occurring cancer and the second leading cause of cancer-related deaths worldwide. There are two basic ways to screen for colorectal cancer. One way is by collecting stool specimens. The second is by evaluating the lining of the colon, which is done by having a Colonoscopy, Sigmoidoscopy, Barium Enema, or a CT Colonography.

A Colonoscopy is considered the most comprehensive method to detect and prevent colorectal cancer.  The procedure consists of inserting a thin, flexible tube into the rectum and evaluating the entire colon.   This method allows the physician to locate and remove precancerous, or adenomatous, colon polyps.

A recent New England Journal of Medicine article titled Colonoscopic Polypectomy and Long-Term Prevention of Colorectal-Cancer Deaths, shows that removal of precancerous polyps through colonoscopy reduced the death rate from colorectal cancer. This study is one of the first research papers looking at how colonoscopy can not only reduce the incidence of colorectal cancer, but can actually decrease mortality or death from it. The study analyzed prospectively 2,602 patients that had initial colonoscopy and precancerous polyp removal. There were only 12 deaths from colorectal cancer reported in the group studied. When compared to a group from the general public with similar age, sex and race, the number of deaths from the disease was about 25 individuals. Resulting in the conclusion that colonoscopy reduced the incidence of colorectal cancer associated death by 53%.

The guidelines from the American College of Gastroenterology for colorectal cancer screening call for all average risk individuals, male and female, to undergo colonoscopy at the age of 50. Other populations with risk factors or symptoms may have varying age for colonoscopy. For example, African Americans as a subgroup are recommended for screening at age 45. Patients need to be aware that there are other methods of colorectal cancer screening if colonoscopy is not available to them. If the other methods have positive findings, however, colonoscopy will then be advised. The overall evidence continues to point to colonoscopy reducing the risk of colorectal cancer and even mortality.