title: Proper muscle layer damage affects ulcer healing after gastric endoscopic submucosal dissection.
abstract: OBJECTIVE
  Endoscopic submucosal dissection (ESD) is the established therapy for superficial gastrointestinal neoplasms. However, management of the artificial ulcers associated with ESD has become important and the relationship between ulcer healing factors and treatment is still unclear. We aimed to evaluate ESD-related artificial ulcer reduction ratio at 4 weeks to assess factors associating with ulcer healing after ESD that may lead to optimal treatment.
  
  
  METHODS
  Between January 2009 and December 2013, a total of 375 lesions fulfilled the expanded criteria for ESD. We defined ulcer reduction rate <90% as (A) poor-healing group; and rate ≥90% as (B) well-healing group. After exclusion, 328 lesions were divided into two groups and analyzed. These two groups were compared based on clinicopathological/endoscopic features, concomitant drugs, and treatment.
  
  
  RESULTS
  Ulcer reduction rate was significantly correlated with factors related to the ESD procedure (i.e. procedure time, submucosal fibrosis, and injury of the proper muscle layer, in univariate analysis. Multivariate logistic regression analysis showed that submucosal fibrosis (F2) (P = 0.03; OR, 16.46; 95% CI, 1.31-206.73) and injury of the proper muscle layer (P = 0.01; OR, 4.27; 95% CI, 2.04-8.92) were statistically significant predictors of delayed healing.
  
  
  CONCLUSIONS
  This single-center retrospective study indicated that ESD-induced artificial ulcer healing was affected by submucosal fibrosis and injury of the proper muscle layer, which induced damage to the muscle layer. Therefore, the preferable pharmacotherapy can be determined on completion of the ESD procedure.
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Horikawa
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Nobuya
authors.initials: N
authors.lastname: Mimori
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Mizutamari
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Yuhei
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shimazu
authors.affiliation: Department of Gastroenterology, Akita University, Graduate School of Medicine, Akita.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sawaguchi
authors.affiliation: Department of Gastroenterology, Akita University, Graduate School of Medicine, Akita.
authors.forename: Shin
authors.initials: S
authors.lastname: Tawaraya
authors.affiliation: Division of Endoscopy, Shizuoka Cancer Center, Shizuoka, Japan.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Igarashi
authors.affiliation: Department of Gastroenterology, Hiraka General Hospital.
authors.forename: Syunji
authors.initials: S
authors.lastname: Okubo
mesh_terms: D000368:Aged; D004210:Dissection / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005753:Gastric Mucosa / Q000473:pathology / Q000601:surgery*; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D008297:Male; D062048:Narrow Band Imaging; D010865:Pilot Projects; D011183:Postoperative Complications / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology / Q000601:surgery*; D013276:Stomach Ulcer / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D025321:Surgery, Computer-Assisted; D013997:Time Factors; D016896:Treatment Outcome; D014945:Wound Healing
keywords: endoscopic submucosal dissection (ESD); pharmacotherapy; proper muscle layer injury; ulcer healing; ulcer reduction ratio