S1315 Anchors Away: Technical Success and Adverse Events Related to Anchored Prong Clips: A Case Series

Introduction: Resection of large colon polyps (>20 mm) is associated with a risk of post-polypectomy delayed bleeding, which may be reduced by defect closure. Achieving complete defect closure with conventional clips can be technically challenging. Anchor-pronged (AP) clips, a novel variation of conventional through-the-scope clips, feature extended prongs designed to improve tissue apposition and facilitate defect closure. This case series evaluated the technical success and adverse events associated with AP clip use for post-resection defect closure. Methods: Thirty-5 adult patients who underwent conventional (hot) EMR, underwater EMR, or ESD for colorectal polyps ≥20 mm with primary defect closure using AP clips were identified at a single tertiary referral center between 2019 and 2024. Technical success and procedure-related adverse events were analyzed. Results: The AP clip cohort had a mean age of 64.5 years, with 48.6% of patients identifying as female. The average polyp size was 36.6 mm, with a mean post-resection defect size of 26.6 mm. Most polyps were located in the right colon (n = 29, 82.8%) and were classified as Paris IIa lesions (n = 20, 57.1%). The majority of patients (n = 28, 80%) were not on anticoagulation therapy. Complete polyp resection was achieved in all 35 cases, with conventional (hot) EMR being the most commonly used resection technique (n = 16, 45.7%). Seventeen cases utilized multiple AP clips for defect closure, with the average number of clips used being 2.8 AP clips (Range 2-6). There were 3 cases of intraprocedural bleeding during polyp resection (8.6%), all of which were successfully managed with AP clip closure technique. Complete defect closure was achieved in all cases. Notably, no intraprocedural bleeding attributable to clip deployment, perforations related to the closure technique, or post-polypectomy delayed bleeding events were observed in this case series. Conclusion: This case series demonstrates a favorable safety profile and high technical success rate for defect closure using AP clips when compared to historical success rates reported for conventional clip closure (60%-80%). An important consideration is whether AP clips provide higher defect closure success rates in technically challenging EMR cases (larger defects, anatomically difficult-to-access sites), where conventional closure techniques have demonstrated limitations. Future studies involving larger cohorts are warranted to validate these findings and address these questions.