Malignant meningioma: clinical and pathological features

Abstract

The records of malignant meningioma were reviewed. In 1 patient, in whom invasion of the brain and pituitary gland was the only unusual feature, the tumor was reclassified as benign. Seven tumors 4 hemangiopericytomas and 2 transitional and 1 syncytial meningioma, were considered to be only borderline-malignant despite necrosis and invasion of the brain, because of few mitoses and regular architecture. Of this group of patients (4 men and 3 women) 2 are alive and well, 3 died after incomplete resections, and 2 succumbed to recurrent tumor that had become inoperable. The other 7 patients (6 men and 1 woman) had lesions classified as histologically frankly malignant on the basis of marked anaplasia and numerous mitoses. These comprised 3 hemangiopericytomas and 3 syncytial and 1 fibrous meningioma. One of these patients is alive and well and the others are dead, 3 as a result of metastases. The initial clinical course of malignant meningiomas tends to be short but is otherwise indistinguishable from that of benign meningiomas. The chances of recurrence and eventual death are high, and extracranial metastases are not rare. The tumors are most often hemangiopericytomas, but not exclusively so, and men are particularly at risk.