Tumors of the central nervous system. Classification of the World Health Organization 2021. Towards a paradigm shift.

The study of central nervous system (CNS) tumors is a subject of great interest and such knowledge is of great importance in medical practice. The classifications of CNS neoplasms began in the mid-19th century, until the World Health Organization (WHO) published, in 1979, the first edition of a useful systematic review for the purpose of establishing a common language for all medical specialties. To date, 5 updated editions of neoplastic taxonomy have been published. The fifth edition, from 2021, consolidates the paradigm shift brought about by molecular advances, although the transition between morphological and molecular biological characterization is still in progress. In this article, the new modifications introduced in the different most frequent families of tumors in pediatrics are analyzed, emphasizing useful information for pediatricians in their daily practice and multidisciplinary consultations.