IDH1 and astrocytoma (excluding glioblastoma): Other relevant molecular characteristics that aid in glioma diagnosis include epidermal growth factor receptor (EGFR) amplification, telomerase reverse transcriptase (TERT) promoter mutations or concurrent gain of chromosome 7 and loss of chromosome 10 in GBMs, and cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) homozygous deletion in IDH-mutant astrocytomas [19].