Nevoid hyperkeratosis of the nipple and areola: a distinct entity.

Although nevoid hyperkeratosis of the nipple and areola was initially described in 1923, there are only case reports or reviews about it; no large series have been documented to date. The clinical features of the reported cases in the literature are not uniform, and it is questioned whether nevoid hyperkeratosis of the nipple and areola is a distinct clinicopathologic entity or a clinical presentation of various dermatoses. We describe 7 cases with hyperkeratotic nevoid lesions localized on the nipple and areola with different clinical features. None of them had any other associated dermatologic or systemic disease. Histopathologic examination was performed in 6 patients. Four of them had common histopathologic features suggesting a distinct entity, namely, nevoid hyperkeratosis of the nipple and areola; 2 of them had histopathologic features consistent with seborrheic keratosis. Seborrheic keratosis presents as sharply demarcated papules or plaques, whereas nevoid hyperkeratosis of the nipple or areola presents as a plaque diffusely involving the nipple or the areola.