title: Effects of additional laparoscopic cholecystectomy on outcomes of laparoscopic gastrectomy in patients with gastric cancer based on a national administrative database.
abstract: BACKGROUND
  Little information is available on the effects of adding laparoscopic cholecystectomy to laparoscopic gastrectomy on outcomes of patients with gastric cancer. The aim of this study is to investigate the effects of adding laparoscopic cholecystectomy to laparoscopic gastrectomy on outcomes in patients with gastric cancer using a national administrative database.
  
  
  METHODS
  A total of 14,006 patients treated with laparoscopic gastrectomy for gastric cancer were referred to 744 hospitals in Japan between 2009 and 2011. Patients were divided into two groups, those who also underwent simultaneous laparoscopic cholecystectomy for gallbladder stones (n = 1484) and those who underwent laparoscopic gastrectomy alone (n = 12,522). Laparoscopy-related complications, in-hospital mortality, length of stay, and medical costs during hospitalization were compared in the patient groups.
  
  
  RESULTS
  Multiple logistic regression analysis revealed that adding laparoscopic cholecystectomy did not affect laparoscopy-related complications (odds ratio, 1.02; 95% confidence interval [CI], 0.84-1.24; P = 0.788) or in-hospital mortality (odds ratio, 1.16; 95% CI, 0.49-2.76; P = 0.727). Multiple linear regression analysis also showed that adding laparoscopic cholecystectomy did not affect the length of stay (unstandardized coefficient, 0.37 d; 95% CI, -0.47 to 1.22 d; P = 0.389). However, adding laparoscopic cholecystectomy was associated with significantly increased medical costs during hospitalization (unstandardized coefficient, $1256.0 (95% CI, $806.2-$1705.9; P < 0.001).
  
  
  CONCLUSIONS
  This study demonstrated that adding laparoscopic cholecystectomy did not affect outcomes of patients undergoing laparoscopic gastrectomy for gastric cancer, although medical costs during hospitalization were significantly increased.
authors.affiliation: Department of Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan. Electronic address: amurata@med.uoeh-u.ac.jp.
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Murata
authors.forename: Kohji
authors.initials: K
authors.lastname: Okamoto
authors.forename: Keiji
authors.initials: K
authors.lastname: Muramatsu
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kubo
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Fujino
authors.forename: Shinya
authors.initials: S
authors.lastname: Matsuda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017081:Cholecystectomy, Laparoscopic / Q000009:adverse effects; D016208:Databases, Factual; D005260:Female; D005743:Gastrectomy; D017048:Health Care Costs; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D013274:Stomach Neoplasms / Q000601:surgery*; D016896:Treatment Outcome
keywords: Administrative database; Gallbladder stones; Gastric cancer; Laparoscopic cholecystectomy; Laparoscopic gastrectomy; Outcomes