title: Endoscopic submucosal dissection for gastric cancer: the influence of hospital volume on complications and length of stay.
abstract: BACKGROUND
  Little information is available about the relationship between hospital volume and the clinical outcome of endoscopic submucosal dissection (ESD) for gastric cancer. The purpose of this study was to investigate the influence of hospital volume on clinical outcomes of ESD using a national administrative database.
  
  
  METHODS
  A total of 27,385 patients treated with ESD for gastric cancer were referred to 867 hospitals between 2009 and 2011 in Japan. We collected patients' data from the administrative database to compare ESD-related complications and length of stay (LOS) in relation to hospital volume. Hospital volume was categorized into three groups based on the number of cases treated over the study period: low-volume hospitals (LVHs, <50 cases), medium-volume hospitals (MVHs, 50-100 cases), and high-volume hospitals (HVHs, >100 cases). These analyses were performed for each location of gastric cancer [upper (cardia and fundus), middle (body), and lower third (antrum and pylorus)].
  
  
  RESULTS
  Significant differences in ESD-related complications among the three hospital volume categories were observed for upper gastric cancer (6.5 % in LVHs vs. 5.2 % in MVHs vs. 3.4 % in HVHs; p = 0.017). Multiple logistic regression revealed that HVHs were significantly associated with decreased relative risk of ESD-related complications in upper gastric cancer (odds ratio for HVHs 0.51; 95 % confidence interval, 0.31-0.83, p = 0.007). However, no significant differences for ESD-related complications were seen for middle and lower gastric cancers among the different hospital volume categories (p > 0.05). Additionally, hospital volume was significantly associated with a decreasing LOS for all locations of gastric cancers (p < 0.001).
  
  
  CONCLUSIONS
  The present study has demonstrated that hospital volume was mainly associated with clinical outcome in patients with ESD for upper gastric cancer. Further studies for successive monitoring of outcomes of ESD should be conducted in the near future.
authors: Department of Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, 807-8555, Japan, amurata@med.uoeh-u.ac.jp.
authors: Atsuhiko
authors: A
authors: Murata
authors: Kohji
authors: K
authors: Okamoto
authors: Keiji
authors: K
authors: Muramatsu
authors: Shinya
authors: S
authors: Matsuda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004210:Dissection / Q000379:methods*; D005260:Female; D005753:Gastric Mucosa / Q000601:surgery*; D005773:Gastroscopy / Q000379:methods*; D061847:Hospitals, High-Volume / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000639:trends*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D013274:Stomach Neoplasms / Q000601:surgery*