title: Improved survival after resectable non-cardia gastric cancer in The Netherlands: the importance of surgical training and quality control.
abstract: BACKGROUND
  In The Netherlands, standardised limited D1 and extended D2 lymph node dissections in the treatment of resectable gastric cancer were introduced nationwide within the framework of the Dutch D1-D2 Gastric Cancer Trial between 1989 and 1993. In a population-based study, we evaluated whether the survival of patients with resectable gastric cancer improved over time on a regional level.
  
  
  METHODS
  We compared 5-year overall and relative survival of patients with curatively resected non-cardia gastric cancer in the regional cancer registry of the Comprehensive Cancer Centre West in The Netherlands before the Dutch D1-D2 trial (1986 to mid 1989; n = 273), during the trial period (mid 1989 to mid 1993; n = 255), and after the trial (mid 1993 to 1999; n = 219), adjusting for prognostic variables.
  
  
  RESULTS
  Unadjusted survival was highest in the post-trial period: 5-year overall and relative survival were 42% and 52%, respectively, compared to 34% and 41% in the pre-trial period, and 39% and 46% in the trial period (p = 0.31 and p = 0.06, respectively). After adjustment for age, gender, tumour site, pT-stage, nodal status and hospital volume, the effect of period on survival was more apparent (p = 0.009). Compared to the pre-trial period, the hazard ratio was 0.83 (95% confidence interval, 0.68-1.02) for the trial period, and 0.72 (0.58-0.89) after the trial. Less than 1% of the patients received adjuvant therapy.
  
  
  CONCLUSIONS
  Survival of patients with curatively resected non-cardia gastric cancer has improved. Standardisation and surgical training in D1 and D2 lymph node dissection are the most likely explanation for this improvement.
authors.affiliation: Leiden Cancer Registry, Comprehensive Cancer Centre West (IKW), Leiden, The Netherlands. p.krijnen@ikw.nl
authors.forename: P
authors.initials: P
authors.lastname: Krijnen
authors.forename: M
authors.initials: M
authors.lastname: den Dulk
authors.forename: E
authors.initials: E
authors.lastname: Meershoek-Klein Kranenbarg
authors.forename: M L E A
authors.initials: ML
authors.lastname: Jansen-Landheer
authors.forename: C J H
authors.initials: CJ
authors.lastname: van de Velde
mesh_terms: D000368:Aged; D004493:Education / Q000592:standards; D004503:Education, Medical, Graduate / Q000592:standards*; D005260:Female; D005743:Gastrectomy / Q000193:education / Q000592:standards; D013502:General Surgery / Q000193:education / Q000592:standards; D006801:Humans; D008197:Lymph Node Excision / Q000193:education / Q000592:standards*; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011786:Quality Control; D012042:Registries; D013274:Stomach Neoplasms / Q000401:mortality* / Q000601:surgery*; D016019:Survival Analysis; D016896:Treatment Outcome