Nevoid hyperkeratosis of the nipple and areola is a rare dermatosis with unknown etiology, (Perez-Izquierdo JM, Vilata JJ, Sanchez JL, et al. Retinoic acid treatment of nipple hyperkeratosis. Arch Dermatol 1990:126:687-688). Only 40 cases have been reported until 1997 (Alpsoy E, Yilmaz E, Aykol A. Hyperkeratosis of the nipple: report of two cases. J Dermatol 1997:24:43-45). The disease has a benign course and may only be a cosmetic problem. Different modalities have been used in the treatment of NHNA. In our case treatment with topical retinoic acid induced an acceptable response. (C) 1999 Elsevier Science B.V. All rights reserved.