Endoscopic En Bloc Versus Piecemeal Resection of Large Nonpedunculated Colonic Adenomas : A Randomized Comparative Trial.

ABSTRACT

BACKGROUND: Endoscopic resection of adenomas prevents colorectal cancer, but the optimal technique for larger lesions is controversial. Piecemeal endoscopic mucosal resection (EMR) has a low adverse event (AE) rate but a variable recurrence rate necessitating early follow-up. Endoscopic submucosal dissection (ESD) can reduce recurrence but may increase AEs. OBJECTIVE: To compare ESD and EMR for large colonic adenomas. DESIGN: Participant-masked, parallel-group, superiority, randomized controlled trial. (ClinicalTrials.gov NCT03962868). SETTING: Multicenter study involving 6 French referral centers from November 2019 to February 2021. PARTICIPANTS: Patients with large (≥25 mm) benign colonic lesions referred for resection. INTERVENTION The patients were randomly assigned by computer 11 (stratification by lesion location and center) to ESD or EMR. MEASUREMENTS The primary end point was 6-month local recurrence (neoplastic tissue on endoscopic assessment and scar biopsy). The secondary end points were technical failure, en bloc R0 resection, and cumulative AEs. RESULTS: In total, 360 patients were randomly assigned to ESD (n = 178) or EMR (n = 182). In the primary analysis set (n = 318 lesions in 318 patients), recurrence occurred after 1 of 161 ESDs (0.6%) and 8 of 157 EMRs (5.1%) (relative risk, 0.12 [95% CI, 0.01 to 0.96]). No recurrence occurred in R0-resected cases (90%) after ESD. The AEs occurred more often after ESD than EMR (35.6% vs. 24.5%, respectively; relative risk, 1.4 [CI, 1.0 to 2.0]). LIMITATION: Procedures were performed under general anesthesia during hospitalization in accordance with the French health system. CONCLUSION: Compared with EMR, ESD reduces the 6-month recurrence rate, obviating the need for systematic early follow-up colonoscopy at the cost of more AEs. PRIMARY FUNDING SOURCE French Ministry of Health.