EGFR and glioblastoma: According to the WHO central nervous system (CNS) 5 classification, glioblastoma is an Isocitrate Dehydrogenase (NADP( +)) (IDH)-wildtype diffuse and astrocytic grade 4 glioma in adults which presents microvascular proliferation or necrosis or mutation of Telomerase Reverse Transcriptase (TERT) promoter or amplification of Epidermal Growth Factor Receptor (EGFR) gene or changes in + 7/ − 10 chromosome copy number1.