Endolumenal full-thickness colon-wall resection using an over-the-scope-clip: three techniques compared in a porcine survival study

Objective: Reliable endoscopic full-thickness resection (EFTR) of the GI-tract would be a desirable adjunct to GI-cancer care. We have recently described an appealing technique for EFTR, using T-tag sutures for accurate tissue retraction and the over-the-scope-clip for pre-resection tissue closure. The aim of this animal survival study was to compare this technique in an either hybrid or purely endolumenal fashion, with a modified method using solely endoscopic suction for retraction.

Methods and Procedures: All survival experiments were performed on female Yorkshire pigs. In Group-A laparoscopic overview was used to facilitate endolumenal colon-wall resection performed with a standard colonoscope. T-tags were endolumenally applied circumferentially to a hypothesized colon-lesion and were used to gently and accurately retract the intestinal wall into the attached over-the-scope-clip system. For pre-resection tissue closure the nitinol-clip was applied as soon as complete intestinal wall retraction had been verified. The inverted colon-wall was then snare-resected and specimens (n ((equals)) 2) were? easily withdrawn from the colon. In Group-B the same technique was performed purely endolumenally without laparoscopic overview (n ((equals)) 5). In Group-C solely suction, instead of T-tag sutures, was used for tissue retraction (n ((equals)) 6). All animals were survived for 14 days followed by necropsy and histological analysis.

Results: EFTR in the colon was achieved in all attempted interventions (13/13). Overall mean intervention time was 33 ± 21 min. The full-thickness colon specimens had a mean diameter of 23 mm ± 6 mm.

In Group-A no signs of leakage or infection were found. At the resection sites normal healing without stenosis was observed macroscopically and histologically. The clips were already passed with the stool. In Group-B the first two EFTR (2/5) also resulted in appropriate healing with the clips already passed. However, the other three resections led to intestinal fistulas (3/5). No related fistula was found in Group-C, with some clips still in place (4/6). However, pure endoscopic suction without T-tags impaired accurate resection with appropriate safety margins barely possible.

Conclusion: Endolumenal full-thickness resection in the colon, using T-tags for tissue retraction and an over-the-scope-clip for pre-resection closure seems appealing but only if laparoscopic overview is used. At this stage pure endolumenal EFTR cannot be recommended.