Pleomorphic adenoma in nasal cavity: immunohistochemical study of three cases.

Intranasal pleomorphic adenoma is a rare neoplasm, and thus only one case report addressed immunohistochemical findings of this neoplasm. To define immunohistochemical features of intranasal pleomorphic adenoma, we studied three cases of the pleomorphic adenoma developed from the nasal septum. Subsequently, immunohistochemical reactivities of the tumor cells for various cytokeratins, glial fibrillary acidic protein (GFAP), S100 protein, alpha-smooth muscle actin (SMA), and vimentin were similar to those of pleomorphic adenoma of the parotid gland. The tumors examined in this study had different histological components, such as predominance of myxoid area, solid area, or tubuloductal structure, but immunoreactivity of both epithelial and myoepithelial tumor cells were the same in the tumors. Therefore, immunoreactivity of the tumor cells were the same among the intranasal pleomorphic adenoma having various histological components.