Radiation-Induced Sphenoid Wing Meningioma After Childhood Medulloblastoma: A Case Report.

Radiation-induced meningiomas (RIMs) are a potential late sequela of pediatric cranial radiotherapy and may arise after a prolonged latency, often 10-30+ years after exposure. We report a 28-year-old male patient treated for medulloblastoma with surgical resection and cranial radiotherapy at age three, who later underwent resection of a right sphenoid wing meningioma at age 16. Following a period of stability, surveillance imaging revealed progressive regrowth at the prior craniotomy site, extending into the superior right orbit. He subsequently presented with dizziness, headaches, and visual changes. MRI demonstrated multifocal enhancing lesions suspicious for radiographic recurrence, involving the anterior right frontal convexity, frontal sinus and ethmoid air cells, and superior right orbit, with mass effect on the orbital structures causing proptosis, as well as an additional right parietal calvarial lesion with adjacent dural thickening and enhancement concerning for a separate meningioma. His admission was further complicated by an acute right posterior cerebral artery infarct, which delayed operative management. This case highlights the complexity of early-latency, multifocal RIM with orbital and sinonasal extension and underscores the need for individualized long-term surveillance in patients treated with cranial radiotherapy during childhood.