Regarding enhancing and non-enhancing tumors, this classification system parallels the original RANO criteria, which employed two distinct assessment systems based on histological classification (high-grade versus low-grade), as in practice, enhancing tumors typically correspond to glioblastoma, IDH-wildtype, while non-enhancing tumors generally align with IDH1/2-mutant low-grade gliomas [87, 88]. This evidence concerns the gene IDH1 and glioma.