RADIOSURGICAL TREATMENT OF RECURRENT HEMANGIOPERICYTOMAS OF THE MENINGES - PRELIMINARY-RESULTS

Hemangiopericytomas of the meninges, classified previously as angiobla stic meningiomas, have a propensity to recur either locally or at dist ant sites within the nervous system after surgical resection. Visceral metastases also develop much more commonly in these lesions than in o ther types of histologically benign meningiomas. The radiosurgical gam ma knife was used to treat five patients with 11 meningeal hemangioper icytomas (seven new, two recurrent, and two residual tumors) after sur gical resection of an initially solitary intracranial lesion. Three pa tients had undergone multiple craniotomies and radiation therapy befor e referral, and two patients underwent a second radiosurgical procedur e for lesions that appeared between 5 and 13 months after the first tr eatment session. Dramatic tumor shrinkage occurred in most patients wi thin 6 to 10 months after treatment. The only treatment-related morbid ity in this series was a partial visual-field defect in one patient wi th a large falx-tentorial junction hemangiopericytoma who had previous ly undergone radiation therapy. Radiosurgery appears to cause dramatic early shrinkage of small and medium-sized intracranial hemangiopericy tomas that have recurred or developed after previous surgery and/or ra diation therapy.