Catálogo de publicaciones - revistas

<jats:p> Tumor classification in neuropathology is a dynamic and complex topic, with many changes emerging in the past 5 years, up to and including the 2021 publication of the 5th edition of the World Health Organization Classification of Tumours of the Central Nervous System (CNS). For pediatric pathologists who will encounter brain tumors with varying frequency, it is important to understand the principles of these classification updates, particularly the inclusion of molecular genetic features and development of a layered, or integrated, diagnosis. This issue of Perspectives in Pediatric Pathology is dedicated to the examination of pediatric brain tumors, and features articles on intraoperative diagnosis and updated information on molecular-based classification for pediatric glial, glioneuronal, ependymal, and embryonal tumors of the CNS. </jats:p>

<jats:p> In 2016, medulloblastoma classification was restructured to allow for incorporation of updated data about medulloblastoma biology, genomics, and clinical behavior. For the first time, medulloblastomas were classified according to molecular characteristics (“genetically defined” categories) as well as histologic characteristics (“histologically defined” categories). Current genetically-defined categories include WNT-activated, SHH-activated TP53 wildtype, SHH-activated TP53-mutant, and non-WNT/non-SHH. In this article, we review the most recent update to the classification of medulloblastomas, provide a practical approach to immunohistochemical and molecular testing for these tumors, and demonstrate how to use key molecular genetic findings to develop an integrated diagnosis. </jats:p>

<jats:p> Since the 1990s, the sheer number of defined central nervous system (CNS) embryonal tumor entities has continuously increased, with the trend accelerating in the most recent editions of the World Health Organization (WHO) Classification of Tumours of the CNS. The introduction of increasingly specific tumor groups is an effort to create more internally homogeneous categories, to allow more precise prognostication, and potentially to develop targeted therapies. However, these ever-smaller categories within an already rare group of tumors pose a challenge for pediatric pathologists. In this article we review the current categorization of non-medulloblastoma CNS embryonal tumors (including atypical teratoid/rhabdoid tumor, cribriform neuroepithelial tumor, embryonal tumor with multilayered rosettes, CNS neuroblastoma, FOXR2-activated, and CNS tumor with BCOR internal tandem duplication) and provide an overview of available ancillary techniques to characterize these tumors. We provide a practical approach to workup and development of an integrated diagnosis for CNS embryonal tumors. </jats:p>