Expanding endoscopic boundaries: Endoscopic resection of large appendiceal orifice polyps with endoscopic mucosal resection and endoscopic submucosal dissection

BACKGROUND Large appendiceal orifice polyps are traditionally treated surgically. Recently, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been utilized as alternative resection techniques. AIM To evaluate the efficacy and safety of endoscopic resection techniques for the management of large appendiceal orifice polyps. METHODS This was a retrospective observational study conducted to assess the feasibility and safety of EMR and ESD for large appendiceal orifice polyps. This project was approved by the Baylor College of Medicine Institutional Review Board. Patients who underwent endoscopic resection of appendiceal orifice polyps >= 1 cm from 2015 to 2022 at a tertiary referral endoscopy center in the United States were enrolled. The main outcomes of this study included en bloc resection, R0 resection, post resection adverse events, and polyp recurrence. RESULTS A total of 19 patients were identified. Most patients were female (53%) and Caucasian (95%). The mean age was 63.3 +/- 10.8 years, and the average body mass index was 28.8 +/- 6.4. The mean polyp size was 25.5 +/- 14.2 mm. 74% of polyps were localized to the appendix (at or inside the appendiceal orifice) and the remaining extended into the cecum. 68% of polyps occupied >= 50% of the appendiceal orifice circumference. The mean procedure duration was 61.6 +/- 37.9 minutes. Polyps were resected via endoscopic mucosal resection, endoscopic submucosal dissection, and hybrid procedures in 5, 6, and 8 patients, respectively. Final pathology was remarkable for tubular adenoma ( n = 10) [one with high grade dysplasia], sessile serrated adenoma (n = 7), and tubulovillous adenoma (n = 2) [two with high grade dysplasia]. En bloc resection was achieved in 84% with an 88% R0 resection rate. Despite the large polyp sizes and challenging procedures, 89% (n = 17) of patients were discharged on the same day as their procedure. Two patients were admitted for post-procedure observation for conservative pain management. Eight patients underwent repeat colonoscopy without evidence of residual or recurrent adenomatous polyps. CONCLUSION Our study highlights how endoscopic mucosal resection, endoscopic submucosal dissection, and hybrid procedures are all appropriate techniques with minimal adverse effects, further validating the utility of endoscopic procedures in the management of large appendiceal polyps.