title: Learning curve and clinical outcome of gastric endoscopic submucosal dissection performed by trainee operators.
abstract: Although endoscopic submucosal dissection (ESD) represents a significant progress in therapeutic endoscopy, little is known about how trainees attain its technical proficiency. The aims of this study were to evaluate the learning curve and clinical outcomes of gastric ESD performed by trainee endoscopists.
  
  
  
  Between April 2009 and March 2014, 334 gastric ESD procedures were performed by seven trainees (42-50 consecutive cases per trainee). The learning curve for gastric ESD was evaluated using the cumulative sum (CUSUM) method. Long-term outcomes were also analyzed.
  
  
  
  The calculated CUSUM learning curve comprised three phases: Phase I (the initial 15 cases), Phase II (the middle 15 cases), and Phase III (the final 20 cases). The resection speed was 5.7 ± 3.2 min/cm2in Phase I, 4.7 ± 2.7 min/cm2in Phase II, and 4.3 ± 2.2 min/cm2in Phase III. The resection speed was significantly faster in Phase II than in Phase I (p = 0.019). The rate of self-completion reached more than 95% in Phases II and III. The overall complete resection rate was 95%, showing no significant differences between the three phases. Local recurrence was diagnosed in none of the patients during a median follow-up of 38 months.
  
  
  
  For the trainees, 30 cases were required to attain a higher technical level of competence in gastric ESD. After the learning curve phase, trainee operators could be expected to complete the procedure successfully with favorable long-term outcomes.
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan. kakushin-tky@umin.ac.jp.
authors.forename: Naomi
authors.initials: N
authors.lastname: Kakushima
authors.affiliation: Clinical Trial Coordination Office, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Mori
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Igarashi
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Kawata
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Takizawa
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Sayo
authors.initials: S
authors.lastname: Ito
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Imai
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Kinichi
authors.initials: K
authors.lastname: Hotta
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Ishiwatari
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsubayashi
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Sunto-gun, Shizuoka, 411-8777, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ono
mesh_terms: D000328:Adult; D000368:Aged; D002983:Clinical Competence; D000069916:Endoscopic Mucosal Resection / Q000193:education*; D005260:Female; D005500:Follow-Up Studies; D005753:Gastric Mucosa / Q000601:surgery*; D006801:Humans; D007564:Japan; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies
keywords: CUSUM; Endoscopic submucosal dissection; Learning curve; Proficiency; Trainee