A Rare Clinical Case of Giant Hemangiopericytoma

Meningeal hemangiopericytomas (HPCs) are aggressive tumors characterized by a high rate of recurrence and delayed metastasis. Despite the malignant nature of these tumors, they often reach a large size with minor clinical presentations. To date, surgical treatment still remains the primary treatment of these tumors. HPC is a malignant tumor arising from pericapillary cells or Zimmerman pericytes. These tumors usually occur in the lower extremities, pelvis, and retroperitoneum. Intracranial HPCs are rare, as they amount to 2—4% of all meningeal tumors and less than 1% of all intracranial tumors. According to the latest 2013 WHO classification of tumors of soft tissue and bone [25, 26], HPCs are included, as a histological variant, to a single nosological form — extrapleural solitary fibrous tumor called “solitary fibrous tumor with predominance of a hemangiopericytoma-like vascular component”. The term hemangiopericytoma is regarded as an obsolete synonym. Despite this fact, taking into account the process localization and based on the current 2007 WHO classification of CNS tumors and a retrospective analysis of the literature on tumors previously diagnosed as HPCs, we reserve the right to use this term in the present study.