IDH1 and glioma: While IDH-wildtype gliomas usually present with high-grade histology and correlate to short survival [7,8], IDH-mutated, 1p/19q-non-codeleted astrocytomas and IDH-mutated 1p/19q-codeleted oligodendrogliomas are usually first diagnosed as low-grade gliomas and associated with longer survival [7,9].