“Neglected nipples”: acanthosis nigricans-like plaques caused by avoidance of nipple cleansing

BACKGROUND Acanthosis nigricans (AN) develops sporadically or in association with obesity, insulin-resistance and dark pigmentary phenotype. Unusual clinical presentations of AN may be diagnostically vexing. OBJECTIVES The aim of the report is to present unusual clinical and dermoscopic pictures of hyper-keratotic, brownish lesions of the nipples resembling acanthosis nigricans. PATIENTS/METHODS Data including clinical and dermoscopic features of two patients with the "neglected nipples": acanthosis nigricans-like (AN-like) hyperpigmented plaques caused by avoidance of nipple cleansing. RESULTS Beside the anamnestic clue, presentation of AN-like plaques in the "neglected nipples" is limited to the breasts, in the absence of involvement of other flexural sites classically affected by AN. Dermoscopy aids the exclusion of a tumor, as it reveals exclusively structureless, brown-gray-black hyperkeratosis in the absence of criteria associated with melanocytic or non-melanocytic skin neoplasms of the nipple. The "neglected breasts" are easily treated by keratolytic creams and hygiene. CONCLUSIONS The "neglected nipples" condition, presenting as bilateral AN-like papules and plaques of the nipples, is due to avoidance of cleansing of the nipple area, resulting in accumulation of keratotic cellular debris.