Unilateral Nevoid Hyperkeratosis of Nipple and Areola in a Filipino Woman: A Case Report and Literature Review

Abstract

Nevoid hyperkeratosis of the nipple and areola (NHNA) is a rare, asymptomatic skin condition characterized by verrucous, hyperpigmented papules, and plaques. It predominantly affects the nipple and areola, often bilaterally. Less than 50 cases have been reported worldwide, with only 39% showing unilateral breast involvement. In the Philippines, a single medical literature from 2014 describes two cases of adolescent-onset NHNA. We report a rare case of a 40-year-old, Filipino woman with a 1-year history of a mildly pruritic, solitary, well-demarcated, irregularly shaped, black papule that progressed into a plaque on her right areola. There was suspicion of cutaneous malignancy due to some of the clinical features of the lesion and lack of response to initial treatment. With a correlation between clinical presentation and histopathologic findings, the features were consistent with NHNA. This is a benign skin condition that can mimic and must be differentiated from malignant tumors. Various treatment modalities were described in different medical literatures, some resulting in recurrence or treatment failure, but there is no standard management for this condition. Skin biopsy is crucial to rule out malignancy in cases presenting with persistent and progressively solitary pigmented lesions that do not respond to topical medications. The usual treatment options based on literature include various topicals, lasers, and surgical procedures. In our case, clobetasol propionate ointment was used. While most published cases show varied responses to topical corticosteroids, the result in our case was significant.