Gliomas, Glioneuronal Tumors, and Neuronal Tumors
Primary brain tumors arising from glial or neuronal cells. This category is subdivided into adult-type diffuse, pediatric-type diffuse, circumscribed astrocytic, and glioneuronal/neuronal tumors.
Subtypes
Astrocytoma, IDH-mutant
Adult-type diffuse infiltrative glioma. Homozygous deletion of CDKN2A/B defines it as CNS WHO grade 4 regardless of histological features.
Diagnostic Molecular Markers
Oligodendroglioma, IDH-mutant and 1p/19q-codeleted
Adult-type diffuse glioma characterized by whole-arm 1p/19q co-deletion.
Diagnostic Molecular Markers
Glioblastoma, IDH-wildtype
The most aggressive adult diffuse glioma. Characterized by necrosis and microvascular proliferation.
Diagnostic Molecular Markers
Diffuse midline glioma, H3 K27-altered
Aggressive pediatric-type high-grade glioma primarily affecting midline structures like the pons (DIPG).
Diagnostic Molecular Markers
Pilocytic astrocytoma
Circumscribed, slow-growing glioma most common in children. Often cystic with a mural nodule.
Diagnostic Molecular Markers
Ganglioglioma
Mixed glioneuronal tumor, highly epileptogenic, commonly found in the temporal lobe.
Diagnostic Molecular Markers
Primary Locations
Clinical Note
Grading and diagnostic criteria listed here are based strictly on the 2021 WHO Classification of Tumours of the Central Nervous System (5th Edition). Many entities now require integrated phenotypic and genotypic characterization for a final diagnosis.