Immunohistochemical findings of sebaceous carcinoma and sebaceoma: retrieval of cytokeratin expression by a panel of anti-cytokeratin monoclonal antibodies.

This study examined immunohistochemical findings of sebaceous carcinoma and sebaceoma. An immunohistochemical study using 13 anti-cytokeratin (CK) antibodies (anti-CK1, 5-8, 10 and 14-20) and 35 cases of sebaceous carcinoma (16 cases on ocular and 19 cases on extraocular regions) and 10 cases of sebaceoma (no cases arose on the eyelids) was performed. Overall, those in ocular lesions were almost the same as those for extraocular lesions in sebaceous carcinoma other than CK8. The findings in sebaceous carcinoma were almost equal to those of sebaceoma. Over 75% of cases with sebaceous carcinoma were positive with anti-CK5 and anti-CK14 antibodies and negative with anti-CK1, CK10, CK15, CK17, CK18 and CK20 antibodies. Most cases (50-75%) of those were positive with CK7 and negative with CK6, CK16, CK19 and CK8. The sensitivity and specificity of immunohistochemical detection of sebaceous carcinoma using the panel of anti-cytokeratin antibodies were lower than those of other antibodies. Immunohistochemical detection of cytokeratins in diagnosing sebaceous carcinoma should be considered to be ancillary to conventional microscopic findings and those of other antibodies.