Changes to the World Health Organization Classification for Pediatric Brain and Spine Tumors

Area of Science:

• Pediatric Neuroradiology
• Molecular Genetics
• Oncology

Background:

• The 2021 World Health Organization (WHO) classification (5th edition) significantly revised central nervous system (CNS) tumor categorization.
• Pediatric brain and spinal cord tumors face substantial changes in classification.
• Integration of molecular genetics is increasingly crucial for CNS tumor management.

Purpose of the Study:

• To outline the major changes in the 5th edition of the WHO CNS tumor classification.
• To highlight the impact of molecular genetics on pediatric CNS tumors.
• To introduce the revised landscape of pediatric CNS tumors.

Main Methods:

• Review of the 2021 WHO classification (5th edition) for CNS tumors.
• Analysis of newly incorporated molecular genetic data.
• Discussion of reclassifications and nomenclature revisions.

Main Results:

• Introduction of new molecularly defined CNS tumors.
• Reclassification of several existing pediatric CNS tumor types.
• Revised nomenclature impacting the understanding and reporting of these tumors.

Conclusions:

• The 5th edition WHO classification represents a paradigm shift in pediatric CNS tumor classification.
• Molecular genetics is fundamental for accurate diagnosis, prognostication, and targeted therapy.
• This revised classification provides a new framework for pediatric neuroradiology.