Immunohistochemistry in diagnosis of extranasopharyngeal angiofibroma originating from nasal cavity: case presentation and review of the literature.

Angiofibromas are rare vascular tumors which originate predominantly in the nasopharynx and occur typically in male adolescents. Extranasopharyngeal sites such as nasal cavity and paranasal sinuses are less frequent. This review article was undertaken to evaluate the incidence, clinical features and management of extranasopharyngeal angiofibromas originating exclusivelly from nasal cavity structures. Our focus of interest was to evaluate the significance of immunohistochemical analysis in diagnosis of such extremely rare neoplasms. In the PubMed and Google Search, we found only 39 cases of nasal angifibroma, 27 males and 12 females from 1980 to 2012. The most prevalent site of origin was nasal septum, followed by inferior and middle turbinate. The commonest symptoms were nasal obstruction and epistaxis. Nasal angiofibromas are clinically distinct from nasopharyneal angiofibromas and can therefore be misdiagnosed. The differential diagnosis includes other vascular lesions, such as lobular capillary hemangioma and sinonasal-type hemangiopericytoma. Although immunohistochemistry is not necessary for differentiation between angiofibroma and capillary hemangioma, that diagnostic procedure may be helpful in distinction from sinonasal hemangiopericytoma. As an ilustration for immunohistochemical analysis, we presented a case of an elderly woman with tumor arising from the middle turbinate, diagnosed as angiofibroma. The staining was positive for CD34, CD31, factor VIII, vimentin and smooth muscle alpha-actin, and negative for desmin.