Clinicopathologic study of 206 cases in Zimbabwe. CT and MR imaging of the buccal space and buccal space masses. Oncocytic differentiation in salivary gland tumours. Metastasis of a superficial spreading malignant melanoma. Immunocytochemical detection of muscle- specific actin, cytokeratin 14, vimentin, and glial fibrillary acidic protein.
Immunocytochemical similarities are also apparent.
Two specific markers for myoepithelial cells in the normal salivary gland, muscle-specific actin and cytokeratin 14, were both variably, independently, and never uniformly expressed in nonluminal cells of pleomorphic adenoma and tumor cells in myoepitheliomas regardless of their morphology. Cytokeratin 14 in addition labels basal cells of excretory ducts. Both muscle-specific actin and cytokeratin 14 preferentially localized to single layers of periductal cells in pleomorphic adenomas, angular, polygonal, and plasmacytoid cells preferentially expressed cytokeratin 14. Similar patterns were noted in the three myoepitheliomas with reasonable expression of the two markers. Only isolated single cells or small groups of plasmacytoid cells in four pleomorphic adenomas with a significant component of these cells and the two plasmacytoid myoepitheliomas immunostained for muscle-specific actin and cytokeratin 14.