Pineal Gland Parenchyma Tumors.

Pineal parenchymal tumors (PPTs) are rare central nervous system neoplasms encompassing a histologically diverse group ranging from WHO grade 1 to 4 lesions. This chapter provides a comprehensive review of the epidemiology, clinical presentation, diagnostic workup, histopathological and molecular features, and treatment strategies of PPTs, with emphasis on surgical approaches and prognostic factors.An extensive review of recent literature was performed, incorporating updated WHO 2021 classifications and data from large multicenter cohorts. Particular attention was given to the inclusion of newly recognized tumor types, such as desmoplastic myxoid tumor of the pineal region, SMARCB1-mutant.PPTs present variably by age and histological subtype. Pineocytomas typically occur in adults and have excellent outcomes following gross total resection. Pineoblastomas, the most aggressive form, are predominantly pediatric and carry a high risk of CSF dissemination and poor prognosis without aggressive multimodal therapy. Pineal parenchymal tumors of intermediate differentiation and papillary tumors show variable behavior and benefit from maximal safe resection and selective adjuvant therapy. Surgical management remains the cornerstone of treatment, with the infratentorial supracerebellar approach favored for midline lesions. Endoscopic-assisted techniques are increasingly used for resection and biopsy, particularly in the presence of obstructive hydrocephalus. Endoscopic third ventriculostomy (ETV) offers an effective minimally invasive solution for hydrocephalus management. Prognostic outcomes are strongly influenced by tumor subtype, extent of resection, and use of adjuvant therapy.Conclusions: PPTs require individualized, multidisciplinary management strategies. Gross total resection remains the optimal surgical goal when safe, while the role of adjuvant therapy is determined by tumor type and grade. Future directions include improving the molecular characterization of rare subtypes and refining endoscopic and minimally invasive techniques. Multicenter studies are needed to establish evidence-based treatment protocols and better define prognostic markers.