Meningiomas

Meningiomas are extra-axial brain tumors of middle-to-late adult life and show a predominance in women. Overall, 90% of meningiomas are benign, 6% atypical, and 2% are malignant. Most patients diagnosed with a meningioma decide to have it removed surgically, and are advised to do so based on their neurologic symptoms. Complete surgical resection is usually curative. For incompletely resected or recurrent tumors not previously irradiated, radiotherapy is administered. Radiotherapy may be administered as either conventional external beam irradiation or stereotactically. Stereotactic radiotherapy (SRT) either as LINAC or gamma knife radiosurgery is increasingly utilized. Advocates of SRT have suggested this therapy as an alternative to surgery particularly in poor surgical risk patients, patients with meningiomas in eloquent or surgically inaccessible locations, and in those patients of advanced age. When the meningioma is unresectable or all other treatments (surgery, radiotherapy) have failed, immunochemotherapy may be considered. Hydroxyurea, alpha interferon, tamoxifen, and mifepristone (RU-486) have been modestly successful in pateints with recurrent meningiomas whereas cyclophosphamide, Adriamycin (Pharmacia and Upjohn, Bridgewater, NJ) and vincristine (CAV), ifosfamide/Mesna (Bristol-Meyers Squibb, Princeton, NJ) or Adriamycin/dacarbazine (DTIC) have been administered to patients with aggressive or malignant meningiomas.