title: The influence of stage migration on the comparison of surgical outcomes between D2 gastrectomy and D3 gastrectomy (para-aortic lymph node dissection): a multi-institutional retrospective study.
abstract: BACKGROUND
  The aim of this study was to determine the influence of stage migration on the outcomes of D2 gastrectomy compared with D3 gastrectomy in advanced gastric cancer.
  
  
  METHODS
  A series of 580 advanced gastric cancer patients (430 D2 gastrectomy and 150 D3 gastrectomy) were registered. The incidence of stage migration and the surgical results of D2 and D3 gastrectomy were compared.
  
  
  RESULTS
  The incidence of N-stage migration was 22.7% and that of pathological stage was 20.7%. Stage-specific survival times of simulated D2 gastrectomy and real D2 gastrectomy were equal. In patients with pN2 tumors measuring 50 to 100 mm in diameter, there was a significant difference in survival between D2 and D3 gastrectomy. However, no difference was observed between D2 and simulated D2 gastrectomy.
  
  
  CONCLUSIONS
  Because there was a high incidence of stage migration in patients after D3 gastrectomy, it may be more feasible to validate comparisons between different levels of lymph node dissection in a randomized controlled trial.
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan. s0714@med.yokohama-cu.ac.jp
authors.forename: Chikara
authors.initials: C
authors.lastname: Kunisaki
authors.forename: Masazumi
authors.initials: M
authors.lastname: Takahashi
authors.forename: Tadao
authors.initials: T
authors.lastname: Fukushima
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nagahori
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Akiyama
authors.forename: Hirochika
authors.initials: H
authors.lastname: Makino
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Otsuka
authors.forename: Hidetaka A
authors.initials: HA
authors.lastname: Ono
authors.forename: Takashi
authors.initials: T
authors.lastname: Kosaka
authors.forename: Ryo
authors.initials: R
authors.lastname: Takagawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shimada
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D005240:Feasibility Studies; D005743:Gastrectomy / Q000379:methods*; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods*; D009367:Neoplasm Staging; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D016019:Survival Analysis; D016896:Treatment Outcome