Primary intracerebral Ewing sarcoma featuring curvilinear calcification: a case report

• First report of curvilinear calcification in primary intracerebral Ewing sarcoma. • Systematic review identifies cystic changes (77.8 %) and marked enhancement (87.5 %) as consistent features. • This unique calcification pattern creates a diagnostic pitfall, closely mimicking oligodendroglioma on imaging. • Aggressive multimodal therapy, including surgery and chemoradiotherapy, enables favorable outcomes. • Provides a crucial imaging clue for diagnosing rare brain tumors in young patients. Ewing sarcoma (EWS) is a highly aggressive malignant tumor that primarily affects bones and soft tissues, with primary intracerebral cases being exceptionally rare. While sporadic cases have been reported, a systematic analysis of their radiological features—particularly calcification patterns—is lacking. We present what we believe to be the first case of a right parieto-occipital EWS exhibiting characteristic curvilinear calcification. A comparative review of 8 intracerebral EWS cases revealed that while cystic changes are common (75 %), curvilinear calcification is unique, and marked enhancement is a consistent finding. Our patient was treated with craniotomy, VDC/IE chemotherapy, and IMRT, and achieved no evidence of disease at 12-month follow-up. This systematic contextualization highlights that curvilinear calcification is a novel diagnostic clue for intracerebral EWS, which generally has a favorable outcome with multimodal therapy.