Molecular Classification and Management of Rare Pediatric Embryonal Brain Tumors

Purpose of review: Malignant embryonal brain tumors (EBTs) of childhood span a wide clinical spectrum but can share remarkably similar morphologic features. This overlap presents significant diagnostic challenges, particularly for tumor entities that are rarely encountered in clinical practice and for which diagnostic criteria were poorly defined. This review will provide an update on the evolving characterization and treatment of rare EBTs.

Recent findings: Rapid advances in genomic tools have led to the discovery of robust molecular markers, and identification of novel tumor types and subtypes for almost all major categories of pediatric brain tumors. These developments have had significant impact on improving the diagnostic classification of the rare EBTs, particularly for tumors with newly recognized C19MC alterations, central nervous system primitive neuroectodermal tumors (CNS-PNET), and pineoblastoma (PB). These important developments in the clinical and molecular understanding of rare EBTs are paving the way for novel therapeutic strategies and improved clinical management.