[Prognostic and predictive factors in high-grade gliomas. Experience at our institution]

To describe and analyse predictive and prognostic factors of overall survival (OS) in high-grade gliomas at our institution.

All patients diagnosed with grade iii (GIII) or grade iv (GIV) gliomas (excluding oligodendrogliomas, oligoastrocytomas or infratentorial gliomas) were prospectively included from November 2010 to August 2014. All were treated with surgery followed by adjuvant radiochemotherapy. The Kaplan-Meier method was used for the statistical analysis, considering a P value ˂.05 to be significant.

89 patients were studied (18 GIII and 71 GIV). The average age was 60 years and 55% were men. The mean Karnofsky score was 80%. The most common location was the frontal lobe (38%). A total of 65% were partial resections. Complete chemotherapy was administered to 74% and complete RT to 83% of patients. Mean OS was 26.8±8.3 months for GIII and 12.5±1 month for GIV. 72 had died by the end of this study. A total of 40% of patients had MGMT methylation, 7% IDH1 mutation and 47% EGFR amplification. Statistically significant variables for OS were: GIII (P=.020), age ˂70 years (P=.040), ˂65 years (P=.013) and ˂60 years (P=.003), Karnofsky ≥70% (P=.029), complete radiotherapy (P=.000), complete resection (P=.001), MGMT methylation (P=.042), IDH1 mutation (P=.007) and EGFR non-amplification (P=.034). Additionally, GIII and GIV subgroups were independently analysed. In GIII, the only significant biomarker for OS was IDH1 mutation, while in GIV, MGMT methylation (P=.023) was significant. Age ≥70 years old was a significant factor in the GIII-subgroup (P=.040) but not for GIV (P=.166).

Data are in line with previous studies, with the exception of age, which does not appear to be significant in GIV.