AIMS: The Ki67 tumour cell proliferation index is an independent prognostic factor in ependymoma patients. Essential prerequisites for validation of the Ki67 index as a histopathological biomarker are the reproducibility of this factor and its prognostic influence by different observers (proof of objective clinical and analytical performance). To this end, the aim was to analyse systematically inter- and intraobserver agreement and reproducibility of the prognostic impact of the Ki67 index in intracranial ependymoma. METHODS AND RESULTS: The study cohort contained 78 cases of intracranial ependymoma. In all cases, the Ki67 index was assessed by four experienced observers (EOs) and by four inexperienced observers (IOs) using the manual hot-spot method. There was considerable agreement on Ki67 index assessment. There was higher observer agreement among EOs compared with IOs. For each observer, survival analysis showed significant association of low Ki67 index with favourable patient outcome. CONCLUSIONS: Our data show that the Ki67 index in intracranial ependymoma is a reproducible and robust prognostic factor and can be considered a promising histopathological candidate biomarker. Attainment of biomarker status requires further translational studies in the context of prospective therapeutic trials.
AIMS: The Ki67 tumour cell proliferation index is an independent prognostic factor in ependymomapatients. Essential prerequisites for validation of the Ki67 index as a histopathological biomarker are the reproducibility of this factor and its prognostic influence by different observers (proof of objective clinical and analytical performance). To this end, the aim was to analyse systematically inter- and intraobserver agreement and reproducibility of the prognostic impact of the Ki67 index in intracranial ependymoma. METHODS AND RESULTS: The study cohort contained 78 cases of intracranial ependymoma. In all cases, the Ki67 index was assessed by four experienced observers (EOs) and by four inexperienced observers (IOs) using the manual hot-spot method. There was considerable agreement on Ki67 index assessment. There was higher observer agreement among EOs compared with IOs. For each observer, survival analysis showed significant association of low Ki67 index with favourable patient outcome. CONCLUSIONS: Our data show that the Ki67 index in intracranial ependymoma is a reproducible and robust prognostic factor and can be considered a promising histopathological candidate biomarker. Attainment of biomarker status requires further translational studies in the context of prospective therapeutic trials.
Authors: Roger E McLendon; Eric Lipp; Diane Satterfield; Melissa Ehinger; Alan Austin; Debra Fleming; Kathryn Perkinson; Michaela Lefaivre; David Zagzag; Benjamin Wiener; Sri Gururangan; Herbert Fuchs; Henry S Friedman; James E Herndon; Patrick Healy Journal: J Neurooncol Date: 2015-01-07 Impact factor: 4.130
Authors: A S Berghoff; A Ilhan-Mutlu; A Wöhrer; M Hackl; G Widhalm; J A Hainfellner; K Dieckmann; T Melchardt; B Dome; H Heinzl; P Birner; M Preusser Journal: Strahlenther Onkol Date: 2014-02-28 Impact factor: 3.621
Authors: Thomas Spanberger; Anna S Berghoff; Carina Dinhof; Aysegül Ilhan-Mutlu; Manuel Magerle; Markus Hutterer; Josef Pichler; Adelheid Wöhrer; Monika Hackl; Georg Widhalm; Johannes A Hainfellner; Karin Dieckmann; Christine Marosi; Peter Birner; Daniela Prayer; Matthias Preusser Journal: Clin Exp Metastasis Date: 2012-10-17 Impact factor: 5.150