Central nervous system hemangiopericytoma, retrospective four year pathology case series.

Hemangiopericytomas (HPC) are uncommon, aggressive, difficult to diagnose tumors mostly found in the extremities and pelvis and very rarely within the Central Nervous System(CNS). CNS HPC closely mimics meningioma, which is a much more frequent benign tumor, while HPC is potentially lethal, thus correct diagnosis of HPC is vital. Due to the very low frequency of CNS HPC, local experience with this tumor is very limited. For this reason a retrospective four year review of CNS pathology cases was performed to observe the frequency of CNS HPC, histopathology, immunohistochemistry, correlate the proportion of HPCto meningiomas and compare these with the literature. Results showed that our past pathologic assessment of HPC as well as the incidence is consistent with the literature, while the ratio of HPC to meningioma was above expected. This is the first local study dealing with the pathology of CNS HPC, which discloses an adequate clinic-pathologic assessment within the UPR premises as reflected by pathologic-epidemiologic findings coincident with the literature. A discrepancy of the HPC to meningioma ratio was found. Further studies are warranted to delve into the etiologies of this discrepancy as the issue has major implications due to the benign and malignant behavior respectively of meningioma and HPC.