RESUMEN
Hemangiopericytoma is a malignant vascular tumor that is rarely seen in the nasal cavity and paranasal sinuses. Biological behavior of the tumor is not completely known and its natural history is not predictable. According to the existing literature, local recurrence rate is not common and distant metastasis is exceedingly rare and majority of patients have a favorable clinical course. We have presented female Persian case of sinonasal hemangiopericytoma in which recurrence of the tumor happened very rapidly after initial removal. It also recurred within two months after reoperation. We have discussed about the characteristics of these tumors and known prognostic factors. We have finally proposed that the sinonasal hemangiopericytoma may have significantly more aggressive clinical course than the previous assumption