These data are important for treatment considerations in patients with IDH-mutant astrocytomas, as they indicate that temozolomide therapy can induce MMR mutation and result in worse outcomes in a subset of these patients, but also suggests a role for immune checkpoint inhibitors to inform potential treatment strategies, although there is disagreement on the efficacy of immunotherapy in the setting of hypermutant gliomas.19,47–49. Here, IDH2 is linked to astrocytoma (excluding glioblastoma).