title: Masaoka staging is of prognostic relevance in type B3 / C thymomas.
abstract: BACKGROUND
  The purpose of this study was to correlate the Ki67 labelling index (LI) with the Masaoka classification and the new WHO-classification in type B3 / C thymomas.
  
  
  METHODS
  Fourteen patients with type B3 / C thymomas were evaluated, and archived specimens were histologically reclassified according to Masaoka staging, the new WHO classification and the Ki-67 LI in a retrospective analysis.
  
  
  RESULTS
  Four patients presented with Masaoka stage II disease (all WHO-type B3), 1 patient had stage III (WHO-type C), 6 stage IVa (3 WHO-type B3 and 3 WHO-type C), and another 3 patients stage IVb (all WHO-type C). The statistical analysis revealed a significant correlation between Masaoka staging and Ki-67 LI (II, III vs. IV; p = 0.007). As well, WHO-classification correlated significantly with Ki-67 LI (B3 vs. C; p = 0.015). Masaoka staging (II, III vs. IV) correlated significantly with survival status (p = 0.0237) in patients with type B3 / C thymoma whereas WHO-classification did not (p = 0.3266). Between survivors and non-survivors there was no statistically significant correlation concerning Ki-67 LI (p = 0.075).
  
  
  CONCLUSIONS
  Our study indicated that the Masaoka staging system is of prognostic relevance in type B3 / C thymomas.
authors.affiliation: Department of Visceral and Vascular Surgery, University of Cologne, Joseph-Stelzmann-Strasse 9, 50931 Cologne, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Luebke
authors.forename: K T E
authors.initials: KT
authors.lastname: Beckurts
authors.forename: C
authors.initials: C
authors.lastname: Wickenhauser
authors.forename: P
authors.initials: P
authors.lastname: Schneider
authors.forename: A H
authors.initials: AH
authors.lastname: Hoelscher
authors.forename: S P
authors.initials: SP
authors.lastname: Moenig
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019394:Ki-67 Antigen; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D013945:Thymoma / Q000145:classification / Q000473:pathology* / Q000628:therapy; D013953:Thymus Neoplasms / Q000145:classification / Q000473:pathology* / Q000628:therapy
chemical_list: D019394:Ki-67 Antigen