The 2016 WHO Classification of Tumours of the Central Nervous System: The Major Points of Revision

• Published in: Neurologia medico-chirurgica Vol. 57; no. 7; pp. 301 - 311
• Main Author: KOMORI, Takashi
• Format: Journal Article
• Language: English
• Published: Japan The Japan Neurosurgical Society 2017; Japan Science and Technology Agency
• Subjects: Brain cancer; Brain tumors; Central nervous system; Central Nervous System Neoplasms - classification; Central Nervous System Neoplasms - diagnosis; Central Nervous System Neoplasms - genetics; Classification; genetics; Glioblastoma; Glioma; Hedgehog protein; histology; Humans; Isocitrate dehydrogenase; Medulloblastoma; Nervous system; Nervous system diseases; new entities; Review; Tumors; Wnt protein; World Health Organization; World Health Organization (WHO); World Health Organization (WHO); genetics; histology; new entities; classification
• ISSN: 0470-8105; 1349-8029
• DOI: 10.2176/nmc.ra.2017-0010

The updated 2016 edition of the World Health Organization (WHO) Classification of Tumours of the Central Nervous System (CNS) uses molecular parameters and the histology to define the main tumor categories for the first time. This represents a shift from the traditional principle of using neuropathological diagnoses, which are primarily based on the microscopic features, to using molecularly-oriented diagnoses. Major restructuring was made with regard to diffuse gliomas, medulloblastomas and other embryonal tumors. New entities that are defined by both the histological and molecular features include glioblastoma, isocitrate dehydrogenase (IDH)-wildtype and glioblastoma, IDH-mutant; diffuse midline glioma, H3 K27M-mutant; RELA fusion-positive ependymoma; medulloblastoma, wingless (WNT)-activated and medulloblastoma, sonic hedgehog (SHH)-activated; and embryonal tumor with multilayered rosettes, C19MC-altered. In addition, some entities that are no longer diagnostically relevant—such as CNS-primitive neuroectodermal tumor—have been deleted from this updated edition. The WHO2016 certainly facilitates clinical and basic research to improve the diagnosis of brain tumors and patient care.