Low Incidence of Aerodigestive Cancers in Patients With Negative Results From Colonoscopies, Regardless of Findings From Multitarget Stool DNA Tests

Abstract

Background & aims: We aimed to compare the incidence of aerodigestive cancers in persons with negative results from colonoscopies and positive vs negative results from multitarget stool DNA tests for colorectal cancer and vs expected incidence. Methods: We performed a retrospective cohort study of 1216 subjects with comprehensive patient records and/or cancer registry data from 3 medical centers in North America. Subjects had no neoplasia or only nonadvanced adenomas, based on screening colonoscopy, and either negative results (concordant with colonoscopy, n = 1011) or positive results (discordant colonoscopy, n = 205) from the multitarget stool DNA test. Outcomes included aerodigestive cancers in discordant vs concordant groups and comparison of observed aerodigestive cancer incidence between the groups and compared with expected incidence for the population, based on the Surveillance, Epidemiology, and End Results (SEER) data. Results: Median follow-up times were comparable between subjects in the discordant (5.3 y; interquartile range, 3.5-5.8 y) and concordant (5.4 y; interquartile range, 3.7-5.8 y) groups. Aerodigestive cancers developed in 5 subjects in the discordant group vs 11 subjects in the concordant group (crude risk ratio, 2.3; 95% CI, 0.8-6.6; adjusted risk ratio, 2.2; 95% CI, 0.8-6.2; P = .151). The incidence of aerodigestive cancer was lower in the concordant group than the expected incidence based on SEER data (risk ratio, 0.4; 95% CI, 0.2-0.6; P = .0008). The incidence of aerodigestive cancer was not significantly greater in the population in the discordant group than the expected incidence based on SEER data (risk ratio, 0.8; 95% CI, 0.3-1.9; P = .599). Conclusions: In a retrospective study with a median follow-up time of 5.4 years, incident aerodigestive cancers were uncommon among subjects with negative findings from colonoscopies, regardless of discordant or concordant results from multitarget stool DNA tests. Patients with negative results from high-quality colonoscopies therefore should not undergo further testing.