RARE CASE OF EXTRACRANIAL SPREAD OF A RECURRENT HEMANGIOPERICYTOMA (GLOMANGIOPERICYTOMA SINONASAL TYPE) TO THE ZYGOMATICO-MAXILLARY COMPLEX: A CASE REPORT.

Hemangiopericytoma (HPC) is an exceedingly rare tumor of uncertain malignant potential. WHO reclassified HPC as a fibroblastic/myofibroblastic tumor, later discontinued the term HPC and renamed Glomangiopericytoma (GPC) 14. Long-term follow up is mandatory because the histologic criteria for prediction of biologic behavior are imprecise. Glomangiopericytoma (GPC) is a rare tumor arising from the pericytes, surrounding capillaries, and accounts for less than 0.5% of all sinonasal tumors. We report a case of recurrent HPC of left maxilla removed via Weber Fergusson approach with total maxillectomy without orbital exenteration and reconstruction with Iliac and antero-lateral thigh flap for a 36-year-old man without any comorbidities, who was referred to our department from neurosurgery with recurrent massive swelling on left face with progressive exophthalmos and nasal obstruction after 2 years of pterional resection of intracranial component. The mass was well circumscribed, but diffused without any fluctuation and firm in consistency. The skin over the tumor was intact and normal. A computer tomography scan showed a large intracranial and extracranial mixed lesion in relation to left maxilla causing displacement of left orbital content but no extension. The tumor was completely removed. During surgery we found a highly vascularised tumor. The histopathologic examination revealed a cellular, highly vascularized tumor. The diagnosis was that of vascular tumor, cellular variant, with haemangiopericytoma-like features. The patient had normal postoperative course of healing and 3 months later he remains asymptomatic, without signs of recurrence or metastases.