IDH1 and astrocytoma (excluding glioblastoma): The latest World Health Organization (WHO) classification criteria divide gliomas into three categories, based on their histopathological and molecular characteristics, i.e., oligodendrogliomas with IDH mutations and chromosome 1p19q co-deletions, astrocytomas with IDH mutations, and glioblastomas with wild-type IDH (Choi et al., 2019).