Impact of antithrombotics on the fecal immunochemical test for colorectal cancer screening : a multi-center Belgian experience.

Background: Impact of antithrombotics on the fecal immunochemical test (FIT) for colorectal cancer (CRC) screening remains unclear.

Methods: Patients undergoing colonoscopy for positive FIT in 2015 were assessed at 3 Belgian centers. Significant findings were advanced polyps (AP) (sessile serrated, tubular or villous adenomas >1cm or high-grade dysplasia) and CRC. False positive FIT and detection of AP/CRC with antithrombotics were calculated.

Results: 510 patients (64% male, median (IQR) age 63.2 (60.2 - 66.4) years) were included. Colorectal pathology in 371/510 (73%) was associated with male gender (70% vs. 48% ; p= .0001) and family history (16% vs. 8% ; p= .02). Antithrombotics in 125/510 (25%) were associated with male gender (78% vs. 59% ; p= .0001), older age (65.2 (62.2-70.3) vs. 62.3 (58.7-66.3) years ; p= .0001) and GI-symptoms (18% vs. 11% ; p= .04). False positive FIT (25% vs. 28% ; p= .52) and detection of AP (42% vs. 36% ; p=.27) or CRC (6% vs. 5% ; p= .69) were similar in patients with vs. no antithrombotics. Use of antithrombotics did not predict a higher chance of colorectal pathology after adjusting for confounders.

Conclusion: Although antithrombotics were prescribed more frequently in male and older patients, detection of AP/CRC was similar. Despite increased GI symptoms, false positive FIT was similar with antithrombotics.