A case of polypoid clear cell acanthoma on the nipple.

Clear cell acanthoma (CCA) is a rare benign epidermal tumor. It usually presents as a flat nodule or dome-shaped plaque and is often localized on the legs of the elderly. We observed an unusual case of polypoid CCA on the nipple of a 14-year-old girl. At present, a few cases of CCA on the nipple area have been reported in the literature. However, CCA presented as a polypoid tumor on the nipple area has been reported very rarely. We herein report the very rare case of polypoid CCA on the nipple and suggest that CCA should be included in the clinical differential diagnosis of polypoid lesions on the nipple.