Endoscopic Submucosal Dissection (ESD) for the Management of Fibrotic Non-Lifting Colorectal Lesions (NLCLs): Results from a Large Multicenter Retrospective Study

<b>Background/Objectives</b>: The management of non-lifting colorectal lesions (NLCLs), often resulting from previous unsuccessful treatments or biopsies, remains challenging due to submucosal fibrosis that prevents adequate lifting. Endoscopic submucosal dissection (ESD) is a viable option for achieving complete resection in such cases. However, when standard ESD is not feasible, conversion to hybrid ESD (H-ESD) has been proposed as a rescue strategy. This study aimed to assess ESD's feasibility, effectiveness, and safety for NLCLs, including cases requiring conversion to H-ESD, when performed by experienced endoscopists in tertiary referral centers. <b>Methods</b>: In this multicenter retrospective study, data from patients with NLCLs treated by ESD/H-ESD between January 2009 and September 2022 were analyzed. The primary endpoint was the recurrence rate (RR). Secondary endpoints included the adverse event (AE) rate, technical success (TS) rate (en bloc resection regardless of technique), complete resection (CR), curative resection (cR) rates, and surgical intervention rate. Predictors of ESD technical success were identified. <b>Results</b>: In total, 178 patients with NLCLs were included (52 previously biopsied, 126 recurrent after previous resection). ESD was used in 111 (62.4%) and H-ESD in 67 (37.6%) cases. During a median follow-up of 373 days (IQR 540), the overall RR was 3.6%. The overall AE rate was 13.4%, and perforation was the most frequent (8.4%). All AEs were successfully managed endoscopically. The TS rate was 71.9%, significantly higher in previously biopsied lesions compared to recurrent ones (78.8% vs. 55.6%, <i>p</i> = 0.04). On multivariate analysis, rectal location (<i>p</i> < 0.001), F1 fibrosis (<i>p</i> = 0.026), and previously biopsied lesions (<i>p</i> = 0.006) predicted ESD TS without the need for conversion to H-ESD. <b>Conclusions</b>: ESD/H-ESD is feasible and safe for NLCLs when performed by experienced operators, with low RR amenable to endoscopic treatment. Previously biopsied lesions, rectal location, and low fibrosis predict ESD TS.