title: Prognostic value of Ki67 index in anaplastic oligodendroglial tumours--a translational study of the European Organization for Research and Treatment of Cancer Brain Tumor Group.
abstract: OBJECTIVE
  To evaluate the prognostic value and clinical utility of Ki67 tumour cell proliferation index in anaplastic oligodendroglial tumours (AOT).
  
  
  RESULTS
  We performed anti-Ki67 immunostaining (MIB-1 antibody) of formalin-fixed and paraffin-embedded tumour tissue specimens of 128 patients with newly diagnosed AOT that were treated in a randomized Phase III trial. Ki67 index was assessed by three independent observers and was correlated to clinical, histopathological and molecular features (including 1p/19q co-deletion, epithelial growth factor receptor gene (EGFR) amplification, isocitrate dehydrogenase (IDH1) mutations, O6-methylguanine-DNA methyltransferase gene (MGMT) promoter methylation, and patient survival times. Intra- and inter-observer agreement of Ki67 index assessment was excellent. Univariable analysis (n = 79) showed that patients with a low Ki67 index had significantly more favourable progression-free survival (PFS) (P-value = 0.004, log-rank test) and overall survival (OS) (P-value = 0.003, log-rank test) than patients with a high Ki67 index, respectively. On multivariable analysis (n = 43), Ki67 index showed no independent association with PFS or OS.
  
  
  CONCLUSIONS
  In AOT the Ki67 index has a strong prognostic impact on univariable analysis, but no independent influence on multivariable analysis. However, further prospective studies including larger numbers of cases and standardized evaluation of Ki67 index in conjunction with other relevant prognostic parameters are needed to draw definitive conclusions.
authors.affiliation: Department of Medicine I, Medical University of Vienna, Vienna, Austria.
authors.forename: Matthias
authors.initials: M
authors.lastname: Preusser
authors.forename: Romana
authors.initials: R
authors.lastname: Hoeftberger
authors.forename: Adelheid
authors.initials: A
authors.lastname: Woehrer
authors.forename: Ellen
authors.initials: E
authors.lastname: Gelpi
authors.forename: Mathilde
authors.initials: M
authors.lastname: Kouwenhoven
authors.forename: Johan M
authors.initials: JM
authors.lastname: Kros
authors.forename: Marc
authors.initials: M
authors.lastname: Sanson
authors.forename: Ahmed
authors.initials: A
authors.lastname: Idbaih
authors.forename: Alba A
authors.initials: AA
authors.lastname: Brandes
authors.forename: Harald
authors.initials: H
authors.lastname: Heinzl
authors.forename: Thierry
authors.initials: T
authors.lastname: Gorlia
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Hainfellner
authors.forename: Martin
authors.initials: M
authors.lastname: van den Bent
mesh_terms: D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D005060:Europe / Q000453:epidemiology; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D015588:Observer Variation; D009837:Oligodendroglioma / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D015996:Survival Rate; D057170:Translational Research, Biomedical
chemical_list: D019394:Ki-67 Antigen