IDH1 and glioblastoma: The malignancies observed in this cohort included 4 IDH-wild-type glioblastomas, 3 IDH-mutant astrocytomas (grade 4), 1 IDH-mutant astrocytoma (grade 3), 1 IDH-mutant astrocytoma (grade 2), and 1 IDH-mutant, 1p/19q-codeleted oligodendrogliomas (grade 2).