Comparison of Hybrid Natural Orifice Transluminal Endoscopic Surgery and Single-Port Laparoscopic Surgery for Sentinel Node Basin Dissection in a Porcine Model

Choice of LECS Procedure for Benign and Malignant Gastric Tumors

Laparoscopic endoscopic cooperative surgery (LECS) refers to the endoscopic dissection of the mucosal or submucosal layers with laparoscopic seromuscular resection. We recommend a treatment algorithm for the LECS procedure for gastric benign tumors according to the protruding type. In the exophytic type, endoscopic-assisted wedge resection can be performed. In the endophytic type, endoscopic-assisted wedge resection of the anterior wall is relatively easy to perform, and endoscopic-assisted transgastric resection, laparoscopic-assisted intragastric surgery, or single-incision intragastric resection in the posterior wall and esophagogastric junction (EG Jx) can be attempted. We propose an algorithm for the LECS procedure for early gastric cancer according to the tumor location. The endoscopic submucosal dissection (ESD) procedure can be adapted for all areas of the stomach, and single-incision ESD can be performed in the mid to high body and the EG Jx. In full-thickness gastric resection, laparoscopy-assisted endoscopic full-thickness resection can be adapted for the entire area of the stomach, but it cannot be applied to the pyloric and EG Jx. In conclusion, surgeons need to select the LECS procedure according to tumor type, tumor location, the surgeon's individual experience, and the situation of the institution while also considering the advantages and disadvantages of each procedure.

Safety and location analysis of transumbilical endoscopic submucosal dissection with single-basin lymph node dissection in the upper gastric body: a porcine model

Background

In our previous study, transumbilical endoscopic submucosal dissection (TU-ESD) was revealed to be feasible, but delayed gastric perforation was observed in 30% of ESD sites. In this study, we aimed to verify locations at which it is feasible to perform TU-ESD in the upper gastric body and to demonstrate the safety of TU-ESD in single-basin lymph node dissection (SBLND).

Methods

In vitro, TU-ESD was performed at three lesion sites (anterior wall, AW; posterior wall, PW; and lesser curvature, LC) in each porcine stomach using an EASIE-R tray (cases = 10). In vivo, TU-ESD was performed with SBLND in 9 pigs. Seven days after the operation, the pigs were sacrificed and examined.

Results

In the in vitro feasibility study, the TU-ESD time was significantly faster in the PW group (5.9 ± 2.0 min) than in the LC group (8.5 ± 1.5 min) (p < 0.05) in all 10 cases. In the in vivo survival study, TU-ESD with SBLND was successfully performed without any complications (N = 9). There were no cases of delayed perforation, and healing ulcers were found in all pigs 7 days after the operation. Ulcer size (5.2 ± 3.5 cm²) was approximately 36% smaller than that observed at the ESD operation site (8.1 ± 1.9 cm²) (p = 0.05). Epithelialization in the margin and healing of the gastric ulcers were confirmed by microscopy.

Conclusions

TU-ESD with SBLND is a feasible and safe method. The upper posterior gastric body could be the most feasible location for performing TU-ESD, perhaps because of the difference in the subcutaneous dissection time.

Feasibility of the trans-umbilical route compared with the trans-oral route in gastric upper body endoscopic submucosal dissection: a porcine model

BACKGROUND

Total gastrectomy is performed for early gastric cancer in the upper body of the stomach because of the high complication rate of endoscopic submucosal dissection (ESD). The aims of the present animal study in pigs were to verify: (1) the feasibility of the trans-umbilical route compared with the trans-oral route in gastric upper body ESD; (2) the non-inferiority of single port laparoscopic lymph node dissection (LLND) compared with multiport LLND; and (3) the safety of 2-basin LLND (upper greater and lesser curvature).

METHODS

We separated the pigs (~40 kg each) into two groups: conventional and experimental (n = 5 per group). We performed ESD in the fundus and upper body anterior wall (UBAW) via the trans-oral route and multiport LLND in the conventional group, and via the trans-umbilical route and single port LLND in the experimental group.

RESULTS

The completion rates, tissue weights, and specimen diameters of both routes showed no statistical differences in either the fundus or the UBAW. The operative time was shorter with the trans-umbilical route than with the trans-oral route in both areas (p < 0.05). In LLND, there were no differences in surgical outcomes between the multiport and single port groups. Intraoperative perforation was seen in the trans-oral route group (n = 1). Delayed perforation was observed in 30 % of the ESD sites.

CONCLUSIONS

The trans-umbilical route is feasible and has lower complication rates than the trans-oral route in gastric upper body ESD. Additionally, single port LLND is not inferior to multiport LLND, and one-side-basin dissection is safer than two-side.