• Diffuse gliomas, separated from the common group of glial tumours, as diffuse astrocytic and oligodendroglial tumours
  • Restructured with incorporation of genetically defined entities
• Medulloblastomas are restructured with incorporation of genetically defined entities
• Other embryonal tumors are also restructured, with incorporation of genetically defined entities
• The term “primitive neuroectodermal tumor” is removed
• Ependymoma - genetically defined variant of RELA fusion positive incorporated.
• Newly recognized entities, variants and patterns added:
  • IDH-wildtype and IDH-mutant glioblastoma (entities)
  • Diffuse midline glioma, H3 K27M–mutant (entity)
  • Embryonal tumour with multilayered rosettes, C19MC-altered (entity)
  • Ependymoma, RELA fusion–positive (entity)
  • Diffuse leptomeningeal glioneuronal tumor (entity)
  • Anaplastic PXA (entity)
  • Epithelioid glioblastoma (variant)
  • Glioblastoma with primitive neuronal component (pattern)
  • Multinodular and vacuolated pattern of ganglion cell tumor (pattern)
• Entities, variants and terms deleted:
  • Gliomatosis cerebri
  • Protoplasmic and fibrillary astrocytoma variants
  • Cellular ependymoma variant
  • “Primitive neuroectodermal tumour” terminology
• Addition of brain invasion as a criterion for the diagnosis of atypical meningioma
• Restructuring of solitary fibrous tumor and hemangiopericytoma (SFT/HPC) as one entity with grades from I to III
• Addition of hybrid nerve sheath tumors and separation of melanotic schwannoma from other schwannomas
• Expansion of entities included in hematopoietic/lymphoid tumors of the CNS (lymphomas and histiocytic tumors)

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Louis DN, et al. The 2016 World Health Organization Classification of Tumors of the Central
Nervous System: a summary. Acta Neuropathol, 2016;6: 803-820