Learning curve for peroral endoscopic myotomy in therapeutic endoscopy experts and nonexperts: Large single‐center experience

Objectives Reports on learning curve for peroral endoscopic myotomy (POEM) in therapeutic endoscopy nonexperts are limited. We aimed to assess the number of cases required to achieve POEM proficiency for endoscopic submucosal dissection (ESD) experts and nonexperts. Methods This is a retrospective study at the largest POEM referral center in Japan. POEM between April 2014 and December 2020 were included. Nonexperts and ESD experts were divided by training phases: A, 1–20; B, 21–40; C, 41–60; D, 61–80; and E, 81–100 cases. Primary outcome was operation time, and the phase to reach target time (83 min) was investigated. Secondary outcomes were clinical success rate, adverse events, and post‐POEM gastroesophageal reflux disease (GERD). Results Five hundred and sixty‐six cases were performed by 14 nonexperts, and 555 cases by 15 ESD experts. As the primary outcome, operation time in nonexperts was: A, 95 (79–115.8); B, 86.5 (71–105); C, 80 (70–100); D, 73 (64.5–100.5); and E, 73.5 (57.8–88.8) min, while in ESD experts: A, 90 (74–128); B, 77 (70–92); and C, 77 (70–93.5) min (median [interquartile range]). Operation time decreased significantly as experience increased in both groups (P