IDH1 and glioblastoma: While extent of resection, age at diagnosis, Karnofsky performance status (KPS), O-6-Methylguanine-DNA Methyltransferase (MGMT) promoter methylation status and presence of an IDH1 or IDH2 mutation are well-validated prognostic factors, [7–9] more recently sex has been shown to be an important prognostic factor for GBM with better survival outcomes observed in females [6, 10].