Abstract
Pineal region tumors are rare and biologically heterogeneous central nervous system neoplasms that occur predominantly in the pediatric population and are associated with significant morbidity and mortality. Among these, pineal parenchymal tumors encompass a spectrum of entities ranging from indolent pineocytomas to highly aggressive pineoblastomas. Recent advances in genomic, epigenomic, and transcriptomic profiling have fundamentally reshaped the understanding of these tumors, moving beyond purely histological classification toward molecularly defined subgroups with distinct biological behavior and clinical outcomes. This review provides a comprehensive overview of the current molecular landscape of pineal region tumors, with a particular focus on genetic predisposition, somatic driver alterations, DNA methylation profiles, and transcriptional programs across pineocytoma, pineal parenchymal tumor of intermediate differentiation (PPTID), pineoblastoma, papillary tumor of the pineal region (PTPR), and desmoplastic myxoid tumor, SMARCB1-mutant. Key oncogenic mechanisms involving microRNA biogenesis disruption, cell-cycle deregulation, MYC/FOXR2-driven transcriptional amplification, PI3K/AKT/mTOR pathway activation, and chromatin remodeling defects are discussed, highlighting their prognostic and therapeutic relevance. In particular, the molecular subdivision of pineoblastoma into distinct subgroups has revealed subgroup-specific vulnerabilities that may be exploitable through targeted therapies. Emerging translational approaches, including molecularly guided treatment strategies and rapid intraoperative sequencing technologies, are also addressed. Despite these advances, the rarity of pineal region tumors continues to limit large-scale clinical trials. Multicenter collaboration and systematic integration of molecular profiling into clinical practice will be essential to improve outcomes for affected children.