EGFR and glioblastoma: It is possible to make a diagnosis of glioblastoma on thebasis of molecular markers alone (mutation of the TERT promoter, amplificationof the EGFR gene, and gain of chromosome 7/loss of chromosome 10) even withouthigh-grade histological findings (necrosis and microvascular proliferation), inwhich case it is considered molecularly defined glioblastoma (Figure 3).