Background and aims The efficacy of colorectal endoscopic mucosal resection (EMR) is limited by recurrence and the necessity for conservative surveillance. Margin thermal ablation (MTA) after EMR has reduced the incidence of recurrence at the first surveillance colonoscopy at 6 months (SC1). Whether this effect is durable to second surveillance colonoscopy (SC2) is unknown. We evaluated long-term surveillance outcomes in a cohort of LNPCPs that have undergone MTA. Methods LNPCPs undergoing EMR and MTA from four academic endoscopy centres were prospectively recruited. EMR scars were evaluated at SC1 and in the absence of recurrence, SC2 colonoscopy was conducted in a further 12 months. A historical control arm was generated from LNPCPs that underwent EMR without MTA. The primary outcome was recurrence at SC2 in all LNPCPs with a recurrence-free scar at SC1. Results 1152 LNPCPs underwent EMR with complete MTA over 90 months until October 2022. 854 LNPCPs underwent SC1 with 29/854 (3.4%) LNPCPs demonstrating recurrence. 472 LNPCPs free of recurrence at SC1 underwent SC2. 260 LNPCPs with complete SC2 follow-up formed the control arm from January 2012 to May 2016. Recurrence at SC2 was significantly less in the MTA arm versus controls (1/472 (0.2%) vs 9/260 (3.5%); p<0.001)). Conclusion LNPCPs that have undergone successful EMR with MTA and are free of recurrence at SC1 are unlikely to develop recurrence in subsequent surveillance out to 2 years. Provided the colon is cleared of synchronous neoplasia, the next surveillance can be potentially extended to 3–5 years. Such an approach would reduce costs and enhance patient compliance. All data and analytical methods relevant to the study are included in the article. Individual participant data will not be shared or made available to other researchers

中文翻译：

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大 （≥20 mm） 无蒂结肠息肉内镜粘膜切除术后切缘热消融对远期复发的影响


背景和目标 结直肠内窥镜粘膜切除术 （EMR） 的疗效受到复发和保守监测必要性的限制。EMR 后的切缘热消融术 （MTA） 降低了 6 个月时第一次监测结肠镜检查的复发率 （SC1）。这种效果是否对第二次监测结肠镜检查 （SC2） 持久尚不清楚。我们评估了一组接受 MTA 的 LNPCPs 的长期监测结果。方法 前瞻性招募来自 4 个学术内窥镜检查中心接受 EMR 和 MTA 的 LNPCP。在 SC1 处评估 EMR 疤痕，在没有复发的情况下，在另外 12 个月内进行 SC2 结肠镜检查。从经过 EMR 但未进行 MTA 的 LNPCP 生成历史对照组。主要结局是所有 LNPCP 在 SC2 处复发，在 SC1 处有无复发性瘢痕。结果 1152 例 LNPCP 接受了 EMR 并完成 MTA，超过 90 个月，直至 2022 年 10 月。854 例 LNPCP 接受了 SC1，其中 29/854 例 （3.4%） LNPCP 显示复发。472 例 SC1 无复发的 LNPCP 接受了 SC2。2012 年 1 月至 2016 年 5 月，260 例 LNPCP 和完整的 SC2 随访组成了对照组。与对照组相比，MTA 组 SC2 的复发率显著减少 （1/472 （0.2%） vs 9/260 （3.5%）;p<0.001））。结论 已成功接受 EMR 和 MTA 并且在 SC1 时没有复发的 LNPCP 不太可能在随后的监测中复发长达 2 年。如果结肠清除了同步肿瘤，下一次监测可能会延长至 3-5 年。这种方法将降低成本并提高患者的依从性。与该研究相关的所有数据和分析方法都包含在文章中。个人参与者数据不会共享或提供给其他研究人员