CLEAR-CELL CARCINOMA OF SALIVARY-GLANDS - IMMUNOHISTOCHEMICAL EVALUATION OF CLEAR TUMOR-CELLS

A total of 14 cases of clear cell carcinoma of salivary glands were ev aluated by immunohistochemical methods using monoclonal antibodies to cytokeratin (K1.1 and K8.12), vimentin, S-100 alpha and beta subunits, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP) , MAM-3 and MAM-6 antigens and proliferating cell nuclear antigen (PCN A), as well as polyclonal antibodies to lysozyme (Ly), lactoferrin (la ) and Alpha-l-antichymotrypsin (a(1)-Ach). Histopathologically, the ca rcinoma was characterized by round or polygonal tumor cells with cytop lasm that does nor stain with hematoxylin and eosin, nuclei with littl e pleomorphism and few or no mitotic figures, and growing in solid she ets, small nests or cords with collagenous stroma. Cytokeratin KL1 and K8.12 was present in few tumor cells with amost negligible to strong reaction in all cases, vimentin in 6, GFAP in 5 cases with multiple-ex pression of cytokeratin K8.12, vimentin and GFAP in 5 cases. S-100 pro tein immunoreactivity was the most prominent feature with more intense reaction of S-100 beta than S-100 alpha subunit. NSE reactivity was s een in 6 cases. Ly, La, a(1)-ch, MAM-S and MAM-6 antigens were localiz ed in clear cells with various reaction intensities. The authors concl ude that the clear tumor cells in clear cell carcinoma of salivary gla nds are not myoepithelial in origin but epithelial or neuroectodermal/ neural crest in origin, showing ductal differentiation at the immunohi stochemical level.