Mucinous eccrine nevus.

A 46-year-old man with an erythematous, tender, swollen patch on the dorsum of his left fourth toe visited us. The biopsied tissue showed a proliferation of normally structured eccrine glands and ducts surrounded with abundant materials confirmed as mucin by toluidine blue stain. Mucinous eccrine nevus is an extremely rare entity, and only two cases have been reported in the literature. We describe a case of mucinous eccrine nevus which was late in onset and presented as a swollen patch.