OC-055 A Novel Technique for full Thickness Laparoendoscopic Excision of Colonic Lesions: an Experimental Pilot Study

Introduction Introduction of a National Bowel Cancer Screening Program in England has resulted in an increasing number of patients diagnosed with endoscopically irresectable colonic polyps. A significant proportion of these patients is referred for hemicolectomy and is subject to a significant risk of morbidity and mortality. Therefore, a less invasive treatment option is required and to address this, we modified a previously reported full thickness laparo-endoscopic excision (FLEX) technique. Methods Surgery was performed in five 70-kg pigs. A simulated colonic polyp was created by endoscopic injection of Spot® and the clearance margin delineated by circumferential placement of mucosal argon plasma coagulator (APC) marks. Full thickness eversion of the colonic wall, including the lesion, was achieved by endoscopic placement of prototype BraceBars (BBs). The everted section was excised using a linear laparoscopic stapler placed below the BBs. The first pig was terminated immediately and others were sacrificed 8 days after surgery. Results The median procedure duration, defined from placement of mucosal APC marks to specimen excision, was 26 min (range 20–31 min). All excised specimens contained three pairs of BBs, included the APC marks and had a median diameter of 5.1 cm (range 4.5–6.3 cm). Postoperative recovery in survival animals was uneventful. Post-mortem evaluation demonstrated well-healed resection sites with no evidence of intra-abdominal infection or inadvertent organ damage. Endoscopic evaluation of anastomoses at post-mortem demonstrated a widely patent lumen without evidence of stenosis at excision sites. Histological examination of the anastomoses showed primary closure by mucosal abbutal and regeneration, with repair and restoration of submucosal continuity. Conclusion This proof-of-concept study has demonstrated the feasibility and safety of a novel full thickness colonic excision technique that is now ready for translation as an alternative to hemicolectomy. The excision size will accommodate most colonic polyps that currently come to surgery. Accurate placement of endoscopic BBs ensures complete excision, reducing the risk of residual disease and recurrence, while laparoscopic overview avoids collateral damage. The ability to preserve mesenteric vasculature and colonic length is likely to result in less morbidity and mortality, better functional outcomes and the approach should reduce treatment costs. Disclosure of Interest None Declared