Nasal glomus tumors: Report of two cases with emphasis on immunohistochemical features and differential diagnosis

We describe 2 cases of nasal glomus tumor that presented as nasal polyps. G rossly, each of the polypectomy specimens consisted of small fragments of p olypoid soft tissue with glistening mucosa. Histopathological examination o f each of the specimens showed sheets and nests of monomorphic round cells intimately associated with capillary-sized blood vessels. The tumor cells w ere strongly cytoplasmic positive for vimentin, smooth-muscle specific acti n, muscle-specific actin. and CD34. Collagen IV showed pericellular positiv ity. Nasal glomus tumors are extremely rare and represent less than 0.5% of nasal nonepithelial tumors. Nasal polyps are common surgical pathological specimens, with the majority of nasal polyps being inflammatory polyps or a respiratory epithelial proliferation. Histologically, many nasal polyps sh ow vascular proliferation with an inflammatory cell infiltrate, which may b e confused with the rare glomus tumor. In addition, other nasal vascular tu mors, in particular nasal hemangiopericytoma and neural tumors, may histolo gically mimic nasal glomus tumors. Copyright (C) 1999 by W.B. Saunders Comp any.