Risk of total metachronous advanced neoplasia in patients with both small tubular adenomas and serrated polyps

Background and Aims: The impact of concomitant small serrated polyps (SPs) on the risk of subsequent neoplasia when small tubular adenomas (TAs) are found is uncertain. Methods: Patients who on index colonoscopy had <= 2 TAs of <10 mm in size in isolation were compared with those with concomitant <= 2 small-sized SPs. SP was inclusive of polyps described by pathology as sessile serrated lesions (SSLs) or proximal hyperplastic polyps (HPs) <10 mm in size. The primary endpoint was the rate of total metachronous advanced neoplasia (T-MAN) compared among the TAs in the isolation group and the groups inclusive of SPs (SSLs or proximal HPs). Results: For patients with TAs and small SPs found concomitantly, the rate of T-MAN was 9.6% (24/251), which was significantly higher than the rate of T-MAN in patients with isolated small TAs (5.2% [59/1138], P = .011). Within the concomitant SP cohort, the rate of T-MAN in the proximal HP subgroup remained significantly increased (9% [19/212]) compared with the isolated small TA group (P = .037). Conclusions: When small TAs are found concomitantly with small SPs, there is an increase in the rate of T-MAN in comparison with isolated TAs. This increase in T-MAN also occurs when small TAs are found in conjunction with small proximalHPs. The presence of concomitant small SPs should be considered in determining surveillance intervalswhen small TAs are identified in colonoscopy screening programs.