Eccrine sweat gland carcinoma of the eyelid with orbital involvement.

A 70-year-old man had a sweat gland carcinoma in his right upper eyelid that was slowly growing, but it clinically remained confined to the lid tissues for a period of 25 years. The tumor ultimately extended deeper into the orbit and invaded the sclera, the optic nerve sheath, and the ethmoidal sinuses. Histopathologic examination disclosed malignant features with a variety of cellular patterns. The results of electron microscopic studies confirmed the origin of the tumor from the eccrine sweat glands.