Meningioma metastatic to the lung

Meningiomas constitute 15% to 18% of all primary intracranial and intraspin al tumors, Distant extracranial metastases are reported to occur in fewer t han 1 in 1000 cases, Of 1992 primary intracranial meningiomas seen at Mayo Clinic Rochester from 1972 through 1994, we identified 3 (0.15%) with docum ented extracranial metastasis, A review of the literature suggests that pre vious craniotomy, venous sinus invasion, local recurrences, histological ma lignancy, and papillary morphology may be risk factors for systemic spread, as demonstrated in our cases, Although rare, metastatic meningioma should be considered in the differential diagnosis of abnormal findings on chest r adiography in patients with known or suspected intracranial meningioma.