AIM: To test a strategy for endoscopic submucosal dissection (ESD) training in animal models designed to overcome the initial learning curve.

METHODS: ESD was attempted in ex vivo and in vivo pig models. Thirty ESD procedures were attempted in the esophagus (n= 9) or the stomach (n= 21). The ex vivo model was used until initial competence was achieved. In the in vivo model, several ESD procedures were performed in up to 3 sessions. The following variables were analyzed: specimen size, complete and en bloc resection rate, time for circumferential incision, time for submucosal dissection, total ESD duration, and complications.

RESULTS: Complete resection was achieved in 28 cases (en bloc 27); 2 could not be completed (one perforation, one technical difficulty). The mean±SD time for circumferential incision was 36.2±16.8 min (range: 8-87 min), and the mean±SD time for submucosal dissection was 45.1±35.7 min (range: 9-196 min). The mean±SD size of the resected specimens was 45.2±17.8 mm. The mean±SD total resection time was significantly increased for the gastric cases performed in the first half of the study (n= 13) than in the second half (n= 8)(98.9±62.4 min vs 61.7±17.6 min, P= 0.04), although the specimen size did not differ.

CONCLUSION: Training in animal models could help endoscopists overcome the learning curve before starting ESD in humans.