Clin Endosc.  2025 Jan;58(1):94-101. 10.5946/ce.2024.108.

Effectiveness of a novel ex vivo training model for gastric endoscopic submucosal dissection training: a prospective observational study conducted at a single center in Japan

• Toba T
• Ishii T
• Sato N
• Nogami A
• Hojo A
• Shimizu R
• Fujimoto A
• Matsuda T

• KMID: 2564023
• DOI: http://doi.org/10.5946/ce.2024.108

Abstract

Background/Aims
The efficacy of endoscopic submucosal dissection (ESD) for early-stage gastric cancer is well established. However, its acquisition is challenging owing to its complexity. In Japan, G-Master is a novel ex vivo gastric ESD training model. The effectiveness of training using G-Master is unknown. This study evaluated the efficacy of gastric ESD training using the G-Master to evaluate trainees’ learning curves and performance.
Methods
Four trainees completed 30 ESD training sessions using the G-Master, and procedure time, resection area, resection completion, en-bloc resection requirement, and perforation occurrence were measured. Resection speed was the primary endpoint, and learning curves were evaluated using the Cumulative Sum (CUSUM) method.
Results
All trainees completed the resection and en-bloc resection of the lesion without any intraoperative perforations. The learning curves covered three phases: initial growth, plateau, and late growth. The transition from phase 1 to phase 2 required a median of 10 sessions. Each trainee completed 30 training sessions in approximately 4 months.
Conclusions
Gastric ESD training using the G-Master is a simple, fast, and effective method for pre-ESD training in clinical practice. It is recommended that at least 10 training sessions be conducted.

Keyword

Gastric endoscopic submucosal dissection; G-Master; Learning curve; Training model

Figure

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  Fig. 1. The G-Master. (A) G-Master body. (B) Mucosa model.

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  Fig. 2. Endoscopic submucosal dissection (ESD) in the G-Master. (A) Pseudolesion with a diameter of 30 mm marked on a mucosal sheet. (B) Injection of glycerol with indigo carmine. (C, D) Pre-cut using a dual knife. (E–K) Mucosal incision and submucosal dissection using an IT-2 knife. (L) Ulceration after ESD.

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  Fig. 3. Area measurement of the resected specimens using ImageJ.

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  Fig. 4. Raw plot of resection speeds for the four trainees.

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  Fig. 5. CUSUM plot of resection speed for the four trainees. CUSUM, cumulative sum.

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