EGFR and diffuse astrocytoma: Based on the 2021 WHO classification of central nervous system tumors, adult IDHwt diffuse astrocytoma can be classified as glioblastoma (GBM), even in the absence of microvascular proliferation or necrosis, if they exhibit at least one of the following molecular markers: TERT promoter mutation, EGFR gene amplification, or chr 7 gain & chr 10 loss [29].