MGMT and astrocytoma (excluding glioblastoma): For example, the methylation of MGMT has been shown to be useful as a prognostic biomarker in some circumstances [70]; EGFR vIII expression enables identification of a subgroup of tumors with more aggressive behavior [71]; and IDH1/IDH2 mutations have strong prognostic value in grade III astrocytomas and in glioblastomas [72].