[Sinonasal-type haemangiopericytoma: a case report].

Sinonasal-type hemangiopericytomas, which comprise less than 0.5% of all sinonasal neoplasms, arise unilaterally in the nasal cavity as polypoid masses with a mean diameter of about 3 cm. A 34-year-old female patient was admitted due to nasal obstruction and epistaxis. A polypoid mass covered with intact mucosa that originated both from the right inferior concha and lateral nasal wall was detected by nasal endoscopy. The tumor, extending from the oropharynx to the nasopharynx, was measured as 3,5x3x2 cm. Although exhibiting characteristic histopathological features and typical clinical symptoms, this case with unexpected immunohistochemical findings can provide a viewpoint on the nature of this kind of tumors.