Hemangiopericytoma of meninges. I. Histopathological variability and differential diagnosis.

A report on morphological variability of meningeal hemangiopericytomas (HP) is presented. 17 cases of HP (12 with intracranial, 5 with spinal localisation) were examined histologically. In 7 cases the tumor recurred, in 2 repeatedly. Metastases were found in 3 cases. As with peripheral HP, a surprising histological diversity is found with meningeal HP. Differential diagnosis can be difficult: Variants of meningioma, fibrous histiocytoma, paraganglioma and other rare richly vascular tumors have to be considered. Although hitherto little known, some additional signs as mucoid change and focal or diffuse fibrosis are helpful for diagnosis. HP of the meninges is considered a well defined entity apart from meningiomas.