IDH1 and glioblastoma: In our validation cohort of 142 patients with IDH wt GBM, age at first diagnosis, radiotherapy, adjuvant chemotherapy, preoperative KPS and GTR, together with a clear trend for SVZ involvement (p = 0.056; HR 1.39 (0.99–1.96)), were predictive for OS, while age at first diagnosis and adjuvant chemotherapy were predictive for PFS (Table 5).