Frontal intradiploic meningioma with progressive intracranial invasion: A rare case report

RATIONALE: Intradiploic meningiomas are a subset of extradural meningiomas that arise in the skull. They are mostly localized in the frontoparietal and orbital regions, and they are often mistaken for primary bone tumors. PATIENT CONCERNS: The patient was a 48-year-old man with headache and a 12-year history of frontal cranium occupation, which was first discovered in 2005 and enlarged in 2009. The patient had a history of fracture in his frontal cranium 12 years ago. The computed tomography and magnetic resonance imaging revealed an occupation and intracranial invasion in frontal cranium. And the angiography showed an occlusion at the anterior part of sagittal sinus. INTERVENTIONS: Bilateral frontal craniotomy, intracranial tumor resection, and cranioplasty were performed. DIAGNOSIS: Histologic examination confirmed an intradiploic ectopic meningioma (World Health Organization Grade I). OUTCOMES: He was discharged with no neurological deficits 3 days after surgery. At the 6-month clinical follow-up, there was no tumor recurrence or other complaints. LESSONS: In this study, we present the case of a frontal intradiploic meningioma with progressive intracranial invasion and review the radiographic and clinical findings of patients with primary intraosseous meningioma.