IDH2 and astrocytoma (excluding glioblastoma): The remaining 5 cases in which loss of CDKN2A was detected comprised one ganglioglioma, one pediatric-type IDH-wildtype infiltrating astrocytoma, one meningioma, one neuroepithelial tumor not otherwise specified (NOS), and one ‘malignant neoplasm, NOS’ (Fig. 3a, b).