Colonoscopies unlikely to detect cancer in right side of colon

Seattle – Colonoscopies have a blind-spot when it comes to detecting cancerous growths on the colon’s right side, according to a study published this week in the Annals of Internal Medicine.

This blind-spot may be the result of how polyps tend to be flatter on the right side of the colon.

The colon-cancer screening test remains highly effective at detecting cancerous tumors or lesions on the colon’s left side, thereby preventing 60% to 70% of deaths related to colorectal cancer, says Dr. Nancy Baxter, the study’s lead author and a colorectal surgeon at St. Michael’s Hospital in Toronto.

The study’s researchers looked at the health records of over 10,000 Ontario residents, who were diagnosed with colon cancer between 1996 and 2001. All of the patients were between the ages of 52 and 90. Of these patients, 7%, or a little more than 700, underwent a colonoscopy six months prior to their death. The control group, for comparison purposes, consisted of 5,000 healthy individuals who had a colonoscopy.

Baxter asserts that colonoscopies are still the best tests currently available for the early detection of colon cancer, which is the second deadliest cancer.