Primary intraventricular osteosarcoma in a 3-year-old boy: report of a case and review of literature.

Introduction: Extraskeletal osteosarcoma (ExOS) is a rare and well-known entity. Three to 4% of ExOSs occur in the head and neck region but anecdotally in the central nervous system (CNS). Primary intracranial osteosarcoma (PIOS) can originate from the skull, brain parenchyma, or meninges.

Case Presentation: A 3-year-old boy with history of head trauma 2 weeks before admission is presented harboring an ExOS in the left temporoparietal region. He was operated with the impression of intraventricular meningioma but turned to be a PIOS without any sources in his skeleton. Tumor recurred after 5 months and patient died in 2 weeks with tumor seeding to the brain stem.

Conclusion: This case is reported to show failure of surgery as the only treatment for these tumors, highlighting the need for more aggressive treatment.