2021 WHO Classification of CNS Tumors: A Comprehensive Course for Pathologists

The field of molecular diagnostics has witnessed significant advancements, leading to substantial changes in the taxonomy, nomenclature, and grading of central nervous system (CNS) tumors as per the 2021 WHO classification. This paradigm shift has introduced 22 new tumor types/subtypes and revised 13 terminologies for tumor types/subtypes. To help pathologists navigate these changes, we present a case-based course that provides a framework for applying contemporary molecular and morphological diagnostic criteria in pediatric and adult brain tumors and pituitary gland neoplasms.

Course Objectives

This collaborative course between the American Association of Neuropathologists and USCAP aims to equip practicing academic and community pathologists, as well as pathologists-in-training, with the knowledge and skills to:

• Apply the 2021 CNS WHO taxonomy, nomenclature, grading, and classification of adult-type diffuse gliomas.
• Integrate morphologic and molecular diagnostic techniques to diagnose pediatric-type diffuse low-/high-grade gliomas.
• Explain the role of integrated molecular diagnosis and histological criteria in the classification of other CNS tumors, including ependymal, dural-based, nerve sheath, and CNS embryonal tumors.
• Summarize the newly described tumor type/subtypes in the 2021 CNS WHO.
• Apply the 2022 WHO classification of pituitary neuroendocrine tumors (PitNETs) according to cell-lineage and cell type.
• Discuss the non-neuroendocrine tumors of the sellar region.
• List the most common nervous system tumors and associated clinical scenarios that should raise suspicion for genetic tumor syndromes.

Expert-Led Sessions

Renowned faculty will lead engaging sessions, ensuring that pathologists become familiar with the major changes in diagnostic criteria and can effectively utilize them in their daily practice. Topics include:

• Sellar Region Tumors 1 (Neuroendocrine) – Sylvia L. Asa, MD, PhD
• Diffuse Gliomas – Arie Perry, MD
• Sellar Region Tumors 2 (Non-Neuroendocrine) – Sylvia L. Asa, MD, PhD
• Meningiomas and Mesenchymal Tumors – Arie Perry, MD
• Ependymal and CNS Embryonal Neoplasms – Daniel Brat, MD, PhD
• Nerve Sheath and Melanocytic Tumors – Melike Pekmezci, MD
• Circumscribed Glial and Glioneuronal Tumors – Daniel Brat, MD, PhD
• Genetic Tumor Syndromes of the Nervous System – Melike Pekmezci, MD

By the end of this comprehensive course, learners will be empowered to navigate the complexities of CNS tumor diagnosis and classification, enhancing their diagnostic accuracy and patient care.