title: Prognostic implications of the seventh edition of the international union against cancer classification for patients with gastric cancer: the Western experience of patients treated in a single-center European institution.
abstract: OBJECTIVE
  Validity of the seventh edition of the American Joint Committee on Cancer/International Union Against Cancer (AJCC/UICC) staging systems for gastric cancer has been evaluated in several studies, mostly in Asian patient populations. Only few data are available on the prognostic implications of the new classification system on a Western population. Therefore, we investigated its prognostic ability based on a German patient cohort.
  
  
  METHODS
  Data from a single-center cohort of 1,767 consecutive patients surgically treated for gastric cancer were classified according to the seventh edition and were compared using the previous TNM/UICC classification. Kaplan-Meier analyses were performed for all TNM stages and UICC stages in a comparative manner. Additional survival receiver operating characteristic analyses and bootstrap-based goodness-of-fit comparisons via Bayesian information criterion (BIC) were performed to assess and compare prognostic performance of the competing classification systems.
  
  
  RESULTS
  We identified the UICC pT/pN stages according to the seventh edition of the AJCC/UICC guidelines as well as resection status, age, Lauren histotype, lymph-node ratio, and tumor grade as independent prognostic factors in gastric cancer, which is consistent with data from previous Asian studies. Overall survival rates according to the new edition were significantly different for each individual's pT, pN, and UICC stage. However, BIC analysis revealed that, owing to higher complexity, the new staging system might not significantly alter predictability for overall survival compared with the old system within the analyzed cohort from a statistical point of view.
  
  
  CONCLUSIONS
  The seventh edition of the AJCC/UICC classification was found to be valid with distinctive prognosis for each stage. However, the AJCC/UICC classification has become more complex without improving predictability for overall survival in a Western population. Therefore, simplification with better predictability of overall survival of patients with gastric cancer should be considered when revising the seventh edition.
authors.affiliation: Klinikum Rechts der Isar der Technischen Universität München, Ismaninger Strasse 22, D-81675 Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Reim
authors.forename: Martin
authors.initials: M
authors.lastname: Loos
authors.forename: Fabian
authors.initials: F
authors.lastname: Vogl
authors.forename: Alexander
authors.initials: A
authors.lastname: Novotny
authors.forename: Tibor
authors.initials: T
authors.lastname: Schuster
authors.forename: Rupert
authors.initials: R
authors.lastname: Langer
authors.forename: Karen
authors.initials: K
authors.lastname: Becker
authors.forename: Heinz
authors.initials: H
authors.lastname: Höfler
authors.forename: Jens
authors.initials: J
authors.lastname: Siveke
authors.forename: Florian
authors.initials: F
authors.lastname: Bassermann
authors.forename: Helmut
authors.initials: H
authors.lastname: Friess
authors.forename: Christoph
authors.initials: C
authors.lastname: Schuhmacher
mesh_terms: D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D016208:Databases, Factual; D005060:Europe / Q000453:epidemiology; D006801:Humans; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000145:classification* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D016019:Survival Analysis