Primary dural hemangiopericytoma with xanthomatous change mimicking meningioma: a case.

Hemangiopericytomas of the Central Nervous system present as a distinct clinicopathologic entity, having been categorized as a “mesenchymal-meningothelial tumour”, according to the current WHO classification. Not only is the lesion rare, but it also bears imaging, macro-micro and immunohistochemical similarities to the commoner tumour-meningioma and to the solitary fibrous tumour and has an indolent biological behaviour unlike the other two. We present a case of a 48 year old lady, diagnosed on imaging as meningioma, which turned out to be a dural hemangiopericytoma after complete histological and immunohistochemical work up. Excluding hemangiopericytoma in lesions presenting as intra-cranial tumours is critical, as the tumour is known for recurrence and metastasis, thereby warranting more aggressive treatment by the neurosurgeons, aiding in better patient care. We report this case not only because of its rarity, but also to show the xanthomatous change the tumour showed, not documented in literature so far.

A Case of Primary Orbital Hemangioperycytoma

Hemangiopericytoma is a rare tumor which originate from the soft tissue. The main sites are lower extremity, pelvic retroperitoneum and especially it is rare to occur primarily in the orbit. It is characterized that hemangiopericytoma possesses the potential of malignancy, but prediction of ultimate behavior is difficult because the clinical course often dose not coincide with histopathologic indicators of malignancy. We experienced a case of primary orbital hemagiopericytoma in a 31-yearold man who had complained diplopia and decreased vision, proptosis, downward and outward deviation of right eye. These symptoms had been occured 7 years ago. MRI examination demonstrated a well-defined tissue mass in superomedial extraconal space in the right orbit. We excised the tumor completely and found it was originated from the vessels with immunohistochemical study utilizing CD34 and Factor VIII-R-Ag as diagnostic marker. Also we confirmed the tumor is a hemangiopericytoma in the Gomoris reticulin stain and EM findings. No recurrence occured for more than 12 months after the initial complete excision. So we present our case with a brief review of the lietrature.