Evaluation of an early-stage innovation for full-thickness excision of benign colonic polyps using the IDEAL framework

Aims: Colectomy is the current approach for patients with endoscopically unresectable benign polyps but risks considerable morbidity. Full-thickness laparoendoscopic excision (FLEX) is a novel procedure, specifically developed to treat endoscopically unresectable benign colonic polyps, which could reduce the treatment burden of the current approach and improve outcomes. However, traditional evaluations of surgical innovations lack methodological rigour. This study reports the development and feasibility of the FLEX procedure in selected patients.

Method: A prospective development study using the Idea, Development, Evaluation, Assessment, Long-term study (IDEAL) framework was undertaken, by one surgeon, of the FLEX procedure in selected patients with endoscopically unresectable benign colonic polyps. Three-dimensional (3D)-CT colonography reconstructions were used preoperatively to rehearse patient-specific, critical manoeuvres. Targetted, full-thickness excision was performed: after marking the margin of the caecal polyp using circumferential endoscopic argon plasma coagulation, transmural endoscopic sutures were used to evert the bowel and resection was undertaken by laparoscopic linear stapling. Feasibility outcomes (establishing 'local success') included evidence of complete polyp resection without adverse events (especially safe closure of the excision site).

Results: Ten patients [median (interquartile range) age: 74 (59-78) years] with polyp median diameters of 35 (30-41) mm, were referred for and consented to receive the FLEX procedure. During the same time frame, no patient underwent colectomy for benign polyps. One further patient received FLEX for local excision of a presumed malignant polyp because severe comorbidity prohibited standard procedures. The FLEX procedure was successfully performed locally, with complete resection of the polyp and safe closure of the excision site, in eight patients. Three noncompleted procedures were converted to laparoscopic segmental colectomy under the same anaesthetic because of endoscopic inaccessibility (two patients) and transcolonic suture failure (one patient).

Conclusions: The FLEX procedure is still under development. Early data demonstrate that it is safe for excision of selected benign polyps. Modifications to transcolonic suture delivery are now required and there is a need for wider adoption before more definitive evaluation can be performed.