Sinonasal hemangiopericytoma of the middle turbinate: a case report and brief review of the literature.

Hemangiopericytomas (HPCs) are rare vascular neoplasms that arise from the pericytes of Zimmerman. They account for 2-3% of all soft tissue sarcomas in humans and they occur mainly in the musculoskeletal system. 15 to 30% of all HPCs occur in the head and neck region. Only 5% are located in the sinonasal region, where they display a more benign behaviour than in other parts of the body. We will describe a case of a right-sided HPC, in the posterior third of the middle turbinate. We will also discuss the epidemiology, the macro- and microscopical characteristics, the clinical and pathological findings and the treatment of this particular neoplasia.