Cliniconathologic diagnosis of oncocytic moeoepidermoid carcinoma in salivary glands

Objective To investigate the elinicopathologic features, diagnosis and differential diagnosis of oncocytic mucoepidermoid carcinoma of the salivary glands. Methods One case of oncocytic mucoepidermoid carci-noma was observed by clinicopathology and immunohistochemistry, followed by discussion through review of the litera-ture. Results The tumor was consisted of acidophilic cells, mucous cells,epidermoid cells and intermediate cells. The neoplastic cells arranged in a sheet, nest and glandular pattern, that were segregated by fibrous tissue. Some area the tumaor was composed of the same types of acidophilie cells,which had abundant finely granular eosinophilic cytoplasm, showed moderate unclear atypia. Histochemistry staining: the mucous secretory cells and some epidermoid cells were positive for PAS. IHC staining, the tumor cells were positive for CK7 and CK20 ,focal positive reaction to CEA, negative for NSE and CgA. Conclusion Oncocytic mucoepidermoid carcinoma is an extremely rare subtype of mucoepidar-moid carcinoma of the salivary glands. Histological examination plays an important role in diagnosis of this tumor. More attention should be paid on the daily practice in order to differentiate this tumor from oncocytic adenoma, pleomorphic adenoma and mucinous cystadenoma. Key words: Salivary neoplasms;  Carcinoma, muccepidermoid;  Oncocytic cells;  Clinicopathology