Innovative noninsufflation EFTR: sufficient endoscopic operative field by mechanical counter traction device

Facilitating endoscopic full-thickness resection for gastric submucosal tumors with a novel snare traction method (with video)

BACKGROUND AND AIM

Endoscopic full-thickness resection (EFTR) is a promising technique in treating gastric submucosal tumors originating from the muscularis propria (SMT-MPs). However, it is challenging without counter-traction.

METHODS

A snare was inserted through the forceps channel to grasp the part of the tumor or the mucosa connected to the tumor. The outer sheath and inner wire of snare in vitro were fixed by a pair of hemostatic forceps. The handle of snare was cut off, and the endoscope was pulled out without affecting the traction state of snare. Snare-assisted EFTR (EFTR-S) was then performed with counter-traction. One hundred and four patients with gastric SMT-MPs who received the procedure of EFTR with or without snare traction method were retrospectively analyzed using univariate and multiple regressions, and covariates were adjusted in the multiple analysis.

RESULTS

Compared with EFTR group (n = 36), EFTR-S group (n = 68) showed a higher operative success rate (95.6% vs 72.2%, P = 0.001), a lower incidence of intraoperative hemorrhage (4.4% vs 16.7%, P = 0.038) and shorter operative time among operative successes (53.6 ± 16.6 min vs 67.7 ± 33.4 min, P < 0.001). Univariate logistic analysis showed that snare traction represented a significant factor, which could improve operative successful rate (odds ratio, 8.3; 95% confidence interval, 2.1 to 32.7; P = 0.002). Postoperative outcomes and adverse events among operative successes were similar between the two groups.

CONCLUSIONS

This novel snare traction method may provide an effective counter-traction and reduce the difficulty of EFTR for gastric SMT-MPs.

Review of Pure Endoscopic Full-Thickness Resection of the Upper Gastrointestinal Tract

Natural-orifice transluminal endoscopic surgery (NOTES) using flexible endoscopy has attracted attention as a minimally invasive surgical method that does not cause an operative wound on the body surface. However, minimizing the number of devices involved in endoscopic, compared to laparoscopic, surgeries has remained a challenge, causing endoscopic surgeries to gradually be phased out of use. If a flexible endoscopic full-thickness suturing device and a counter-traction device were developed to expand the surgical field for gastrointestinal-tract collapse, then endoscopic full-thickness resection using NOTES, which is seen as an extension of endoscopic submucosal dissection for full-thickness excision of tumors involving the gastrointestinal-tract wall, might become an extremely minimally invasive surgical method that could be used to resect only full-thickness lesions approached by the shortest distance via the mouth. It is expected that gastroenterological endoscopists will use this surgery if device development is advanced. This extremely minimally invasive surgery would have an immeasurable impact with regard to mitigating the burden on patients and reducing healthcare costs. Development of a new surgical method using a multipurpose flexible endoscope is therefore considered a socially urgent issue.

Novel NOTES Techniques and Experimental Devices for Endoscopic Full-thickness Resection (EFTR)

Natural orifice transluminal endoscopic surgery (NOTES), in which a flexible endoscope is used to perform operations that have traditionally required laparoscopic surgery, has garnered attention as a minimally invasive surgery that does not leave a surgical wound on the body. Among the various forms of NOTES, endoscopic full-thickness resection (EFTR) is an ultraminimally invasive endoscopic surgery that allows for radical resection, which is an extension of endoscopic submucosal dissection and involves full-thickness excision of a tumor of the gastrointestinal tract wall. With further development of the equipment, including full-thickness suture instruments, nonexposed EFTR could be a feasible surgical procedure.

Endoscopic Submucosal Dissection (ESD) and Related Techniques as Precursors of "New Notes" Resection Methods for Gastric Neoplasms

Endoscopic full-thickness resection for subepithelial tumors is one of the more attractive proposed methods for less-invasive transluminal surgery but remains challenging in terms of safety and feasibility. Currently, laparoscopic endoscopic cooperative surgery is thought to be a more clinically acceptable approach. In targeting cancers, however, more advanced nonexposure techniques are required to avoid the risk of iatrogenic tumor seeding. By combining these techniques with possible regional lymphadenectomy using sentinel node navigation surgery, an ideal minimally invasive, function-preserving gastric resection can be achieved even in possible node-positive cancers. Further development for this type of advanced endoscopic surgery is expected.

Endoscopic full-thickness resection: Current status

Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices.

Current innovations in endoscopic therapy for the management of colorectal cancer: from endoscopic submucosal dissection to endoscopic full-thickness resection

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for colorectal cancer. However, due to technical difficulties and an increased rate of complications, ESD is not widely used in the colorectum. In some cases, endoscopic treatment alone is insufficient for disease control, and laparoscopic surgery is required. The combination of laparoscopic surgery and endoscopic resection represents a new frontier in cancer treatment. Recent developments in advanced polypectomy and minimally invasive surgical techniques will enable surgeons and endoscopists to challenge current practice in colorectal cancer treatment. Endoscopic full-thickness resection (EFTR) of the colon offers the potential to decrease the postoperative morbidity and mortality associated with segmental colectomy while enhancing the diagnostic yield compared to current endoscopic techniques. However, closure is necessary after EFTR and natural transluminal endoscopic surgery (NOTES). Innovative methods and new devices for EFTR and suturing are being developed and may potentially change traditional paradigms to achieve minimally invasive surgery for colorectal cancer. The present paper aims to discuss the complementary role of ESD and the future development of EFTR. We focus on the possibility of achieving EFTR using the ESD method and closing devices.

Pure endoscopic full-thickness resection with peritoneoscopy and omentectomy

OBJECTIVE

To investigate surgical procedures for pure endoscopic full-thickness resection (EFTR) using a flexible endoscope and a prototype of a full thickness suturing device in animal experiments.

METHODS

Six beagles were divided into two groups: sutured with over-the-scope-clip (OTSC group, n = 3) and with a prototype of the double-arm bar suturing system (DBSS group, n = 3). The peritoneoscopy, omentectomy and EFTR procedures were performed through the transgastric route. We examined the surgical procedures required to accomplish pure EFTR and survival rates of these dogs after EFTR.

RESULTS

The duodenal balloon occlusion method maintained a sufficient endoscopic view during peritoneoscopy. Grooves of 10-mm wide were created around the tumor down to the third layer for treating all blood vessels and adding landmark for full-thickness resection lines. Using the muscle layer thin-cutting method, hyaluronic acid was locally injected into the muscle layer and fine incisions were made. Creating tiny perforations provided safe access to the abdominal cavity. Although it was difficult to suture the resected site safely in the OTSC group, the DBSS prototype was useful and reliable for closing there section sites with 3-0 absorbable thread. After EFTR there were no complications in the DBSS group and the dogs were in good health on POD 30, whereas in the OTSC group two dogs died due to dehiscence and gastric juice leaks. Postmortem examinations showed abscess around the suturing sites and two OTSC were detached from the suturing sites.

CONCLUSIONS

Pure EFTR is feasible with DBSS when systematic methods are established. The high safety of full-thickness resection suturing will permit their clinical application in the near future.

Feasibility of pure EFTR using an innovative new endoscopic suturing device: the Double-arm-bar Suturing System (with video)

BACKGROUND

Endoscopic full-thickness resection (EFTR) requires a reliable full-thickness suturing device and an endoscopic counter-traction device to prevent the collapse of the digestive tract.

OBJECTIVE

The present study aimed to assess the reliability of newly developed flexible endoscopy suturing devices and the feasibility of pure EFTR.

METHODS

A total of 30 EFTRs were performed and allocated to three groups (N = 10 for each group). The full-thickness sutures were placed using over-the-scope clips (OTSCs), hand-sewn sutures, or the Double-arm-bar Suturing System (DBSS). Air leak tests were conducted in the three groups. The times required for the placement of one OTSC suture and single-stitch simple interrupted sutures (hand-sewn and DBSS sutures, respectively) were also compared.

RESULTS

All 30 full-thickness sutures were completely and successfully placed. Regarding the air leak tests, the Mann-Whitney U test showed significant differences between OTSC and hand-sewn sutures (p = 0.003). There was also a significant difference between OTSC and DBSS sutures (p = 0.023). There was no significant difference between hand-sewn and DBSS sutures (p = 0.542). A significant difference was found in the suture time for single-stitch simple interrupted sutures among the OTSC, hand-sewn, and DBSS sutures. The Mann-Whitney U test revealed a significant difference between OTSC and hand-sewn sutures (p = 0.0001). There was no significant difference between OTSC and DBSS sutures (p = 0.533), while a significant difference was found between hand-sewn and DBSS sutures (p = 0.0001).

CONCLUSIONS

Pure EFTR is feasible if the mechanical counter traction system is used to expand a small operative field and DBSS is used to make full-thickness sutures. The high safety of full-thickness resection and full-thickness suturing allows for clinical applications of this method.