IARS1 and anaplastic oligodendroglioma: Accordingly, expression of SSTR2A protein (any level, IRS ≥ 1) was significantly associated with longer PFS (p = 0.010) and OS (p = 0.007) among the subgroup of anaplastic oligodendroglioma, IDH-mutant and 1p/19q-codeleted (Fig. 4b).