Risk of total metachronous advanced neoplasia at surveillance colonoscopy after detection of serrated lesions: a matched case–cohort study

Abstract

Background and Study Aims: Serrated lesions (SLs), including sessile serrated lesions (SSL) and traditional serrated adenomas (TSA) have become subject of increased interest for their role as CRC precursors. Primary aim was to evaluate the presence of total metachronous advanced neoplasia (T-MAN) at follow-up in patients with index SL compared to a matched cohort without SL. Patients and Methods: Patients 45-74y with SLs were matched 2:1 by sex; age; synchronous polyps (high-risk adenoma [HRA], low-risk adenoma [LRA], no-adenoma); timing of index, to patients without SL. Primary outcome was presence of T-MAN (advanced adenoma or high-risk SL) at follow-up. Secondary outcomes included presence of T-MAN stratified by synchronous polyps and SL characteristics. Results: 1425 patients were included (475 patients, 642 SLs; 950 controls (median follow-up 2.9 vs 3.6y). The SL group had greater risk of T-MAN compared to the non-SL group [Hazard-ratio (HR)=6.1 (95%confidence-interval (CI)3.9-9.6)]. Patients with SL+HRA had higher risk of T-MAN compared to HRA alone [HR=2.6 (95%CI 1.4-4.7)], as well as patients with SL+LRA compared to LRA alone [HR=7.0 (95%CI 2.8-18.4)], and SL without adenoma compared to no-adenoma [HR=14.9 (95%CI 6.5-34.0)]. Presence of proximal SSL [HR=9.3 (95%CI 5.4-15.9)], large SSL [HR=17.8 (95%CI 7.4-43.3)] and proximal large SSL [HR=25.0 (95%CI 8.8-71.3)], but not distal SSL, was associated with greater risk for T-MAN. Conclusion: Patients with SLs are at greater risk for developing T-MAN regardless of synchronous adenomas. Patients with SL and HRA, and those with large or proximal SSLs appear to be at greatest risk for T-MAN.

Large serrated polyps indicate a greater risk of advanced metachronous colorectal neoplasia than high-grade adenomas

“…This study is part of a larger project comparing outcomes for colonoscopy findings. Part of the study cohort has been previously reported, however, there are no data overlap in reported outcomes 15 .…”

Endoscopic surveillance after resection of sessile serrated lesions: so far, so good?

“…In this issue of Endoscopy, Djinbachian et al present a large retrospective matched case-cohort analysis of the prevalence of total metachronous advanced neoplasia (T-MAN) among patients who underwent resection of an SSL compared with patients without SSLs [7]. T-MAN is an "umbrella" outcome that includes both metachronous advanced adenomas and metachronous advanced SSLs.…”