Immunohistochemical localization of epidermal growth factor receptor and epithelial antigen in tumors of the human conjunctiva, eyelid, lacrimal gland, and orbit.

Background: Increased numbers of epidermal growth factor (EGF) receptors are observed in squamous cell carcinomas of human lung, head, neck, and cervix. We studied the presence of EGF receptors and epithelial antigen in some ophthalmic lesions.

Methods: Immunohistochemical staining for EGF receptors was assessed in tumors of human conjunctiva, eyelid, lacrimal glands, and orbit with monoclonal antibodies (EGF-R1 and clone 29.1). Reactivity of Ber-EP4, which recognizes epithelial antigen, was also examined.

Results: Strong staining of EGF-R1 and clone 29.1 and weak to moderate staining of Ber-EP4 were demonstrated in conjunctival squamous cell carcinomas. Cell membranes of conjunctival papilloma were moderately or strongly stained with these antibodies. Ductal components in sebaceous gland adenoma of the eyelid and pleomorphic adenoma of the lacrimal gland were positively stained. The antibodies did not bind to reactive lymphoid hyperplasia of the orbit and Wegener's granulomatosis. Relatively good correlation for immunostaining reaction was observed among EGF-R1, clone 29.1, and Ber-EP4 in each tumor.

Conclusion: Immunostaining using EGF-R1, clone 29.1, and Ber-EP4 may be useful in differentiating epithelial tumors from non-epithelial lesions. Strong immunostaining for EGF receptor may be the hallmark of epidermoid malignancy.