Study: Risk of Colorectal Cancer in 40s Supports Start of Screening at 50

Indiana University researchers report the risk of precancerous polyps and colorectal cancer in individuals in their 40s is low and there appears to begin screening persons at average risk before age 50.

The findings of their study, reported in the New England Journal of Medicine, support current colon cancer screening guidelines -- that individuals begin having a colonoscopy every 10 years starting at age 50.

Dr. Thomas F. Imperiale of Indiana University School of Medicine in Indianapolis and colleagues evaluated colonoscopy data for 906 men and women aged 40 to 49 years, none of whom had symptoms or a family history of colorectal cancer.

While 21 percent of the participants had polyps or other suspicious looking lesions or growths, none was found to have colorectal cancer, according to the researchers.

Imperiale reported that colonoscopic detection of colorectal cancer is sufficiently uncommon in asymptomatic persons in their 40s that if the results of the study were applied to the general population, " at least 250 persons, and perhaps 1000 or more, would need to be screened to detect one cancer in this age group.

"The low yield of screening colonoscopy in this age group is consistent with current recommendations about the age at which to begin screening in persons at average risk," the researchers concluded.

Other sources: New England Journal of Medicine