Table 1.
Glioma classification according to World Health Organization (WHO) 2021.
| Tumor Type | CNS WHO Grade |
|---|---|
| Adult-type diffuse gliomas | |
| Astrocytoma, IDH-mutant | 2, 3, 4 |
| Oligodendroglioma, IDH-mutant, and 1p/19q-codeleted | 2, 3 |
| Glioblastoma, IDH-wildtype | 4 |
| Pediatric-type diffuse low-grade gliomas | |
| Diffuse astrocytoma, MYB- or MYBL1-altered # | 1 |
| Angiocentric glioma | 1 |
| Polymorphous low-grade neuroepithelial tumor of the young # | 1 |
| Diffuse low-grade glioma, MAPK pathway-altered *# | - |
| Pediatric-type diffuse high-grade gliomas | |
| Diffuse midline glioma, H3 K27-altered | 4 |
| Diffuse hemispheric glioma, H3 G34-mutant # | 4 |
| Diffuse pediatric-type high-grade glioma, H3-wildtype and IDH-wildtype # | 4 |
| Infant-type hemispheric glioma *# | - |
| Circumscribed astrocytic gliomas | |
| Pilocytic astrocytoma | 1 |
| High-grade astrocytoma with piloid features *# | - |
| Pleomorphic xanthoastrocytoma | 2, 3 |
| Subependymal giant cell astrocytoma | 1 |
| Chordoid glioma | 2 |
| Astroblastoma, MN1 altered * | - |
| Ependymal tumors |
# Newly recognized tumor types in 2021 WHO classification of CNS tumors. * Definitive CNS WHO grade not established.