An 81-year-old man had a keratotic eyelid lesions for 20 years. He eventual
ly sought treatment by ophthalmic plastic surgery. Clinically, the lesion r
esembled a keratoacanthoma. Findings from histologic examination of the exc
ision biopsy specimen showed a squamous cell carcinoma. The lesion was comp
letely excised. This case demonstrates the difficulty in making a correct c
linical diagnosis of a keratotic eyelid lesion. Performing a histologic exa
mination of nonregressed keratotic lesions is essential to exclude a squamo
us cell carcinoma.