CD34-positive expression in benign nasal glomus tumour: two case reports and a literature review.

Nasal glomus tumours are extremely rare neoplasms with poorly understood histogenesis, but which are clinically recognized as benign. The neoplastic cells of glomus tumours resemble normal glomus cells and are arranged around a varying number of thin-walled, sometimes branching, capillaries. CD34 is known to be a marker of tumour progenitor cells. In this report, two cases of benign nasal glomus tumour are presented. The tumours were excised completely via endoscopic endonasal surgery under local anaesthesia. During surgery, there was little bleeding and the post-surgical course for both patients was uneventful. Tumour cells from both cases were positive for α-smooth muscle actin, actin, vimentin and CD34 protein. Thus, CD34 positivity against a background of other immunohisto chemical markers is helpful in the differential diagnosis of glomus tumours.