Immunohistochemistry in ocular carcinomas.

BACKGROUND

The distinction between ocular sebaceous carcinoma, poorly differentiated ocular squamous cell carcinoma and ocular basal cell carcinoma can be challenging. An appropriate immunohistochemical panel may help to differentiate these lesions.

METHODS

To determine the distribution and use of several immunostains in these specimens, formalin-fixed, paraffin-embedded tissue from several of each was studied using an immunohistochemical technique.

RESULTS

Positive staining for cytokeratin (CK)7 was seen in 100% of sebaceous carcinomas, 77.8% of basal cell carcinomas and 67.7% of squamous cell carcinomas. One hundred percent of sebaceous and basal cell carcinomas were positive for cytokeratin CAM 5.2, while only 83.3% of squamous cell carcinomas were positive. Using epithelial membrane antigen (EMA), 100% of squamous cell carcinomas and 80% of sebaceous carcinomas were positive, while basal cell carcinomas were uniformly negative. One hundred percent of basal cell carcinomas and 80% of sebaceous carcinomas were positive for Ber-EP4, while all squamous cell carcinomas were negative. Finally, 77.8%, 20% and 16.7% of basal cell carcinomas, sebaceous carcinomas and squamous cell carcinomas showed immunoreactivity for the androgen receptor.

CONCLUSION

An EMA positive, Ber-EP4 positive immunophenotype supports sebaceous carcinoma, EMA positive, Ber-EP4 negative result supports squamous cell carcinoma and an EMA negative, Ber-EP4 positive result supports basal cell carcinoma.