Three-Year Interval Feasible for Stool-Based CRC Screening in Low-Risk People

TUESDAY, Dec. 6, 2022 (HealthDay News) — A three-year interval for multitarget stool DNA (mt-sDNA) colorectal cancer (CRC) screening for those at average risk appears clinically appropriate, according to a study published online Oct. 7 in Cancer Prevention Research.

Thomas F. Imperiale, M.D., from the Indiana University School of Medicine in Indianapolis, and colleagues examined the clinical utility of a three-year interval for mt-sDNA testing. The analysis included 2,044 candidates for CRC screening whose providers prescribed the mt-sDNA test (April 2015 to July 2016), with participants testing positive completing a colonoscopy and those testing negative followed annually for three years.

The researchers found that at baseline, 13.9 percent had a positive mt-sDNA result and 86.1 percent were negative. Among the year 3 intention-to-screen cohort (591 with valid mt-sDNA and colonoscopy results), there were no CRCs and 63 advanced precancerous lesions (34.9 percent detected by mt-sDNA). Respective Predictive Summary Index values were 0 and 9.3 percent. For CRC, the observed three-year yield was lower than expected, while the yield for advanced precancerous lesions was higher than expected.

“The study findings suggest that repeat mt-sDNA screening at three years may be considered clinically appropriate, as evidenced by the reduced number of observed versus expected CRCs, while identifying advanced precancerous lesions at a rate consistent with the pivotal study,” the authors write.

Several authors disclosed financial ties to Exact Sciences, which funded the study.