Risk score decides who gets invasive colorectal screening

A new risk assessment system could decide who needs to be screened for colorectal cancer with invasive colonoscopy versus a noninvasive test, according to a new study in the Annals of Internal Medicine.

Researchers at Indiana University aimed to create a colorectal cancer risk assessment system that benefits from the fact that 85% of the population is classified as "average risk" for colorectal cancer.

Colorectal cancer screening tests are cost-effective but used inefficiently because of the current inability to tailor screening methods precisely according to risk, wrote lead author Dr. Thomas Imperiale and colleagues (Ann Intern Med, September 1, 2015, Vol. 163:5, pp. 339-346).

The researchers evaluated average-risk individuals who were undergoing initial screening colonoscopy in Midwestern endoscopy units and practices. The risk assessment score was based on known risk factors for colorectal cancer and advanced precancerous polyps, including age, gender, family history of colorectal cancer, smoking history, and waist circumference, the authors wrote.

Participants were categorized into risk levels ranging from very low to high. The results suggested that less-invasive tests such as flexible sigmoidoscopy might be appropriate for low-risk patients, while higher-risk groups might need a colonoscopy.

A key challenge is getting providers comfortable enough to use the scoring system and direct tests accordingly, according to Imperiale.