TERT and glioblastoma: The recent (2021) WHO classification of central nervous system (CNS) tumors applies molecular criteria that allow for a diagnosis of GBM, CNS grade 4, of IDHwt astrocytic gliomas, even in the absence of high-grade histopathologic features, when at least one of the following molecular features is present: concurrent EGFR amplification, chromosome 7 gain/10 loss (+ 7/ − 10), or a TERT promoter mutation10.