Pigmented lesion of the nipple - a clinicopathological challenge.

Differential diagnoses of pigmented lesions of the nipple include melanocytic nevus, melanosis of the nipple, seborrheic keratosis, pigmented basal cell carcinoma, melanoma and Paget disease. The histologic exam with appropriate immunohistochemistry is a fundamental tool to achieve a correct diagnosis. We present a patient with a pigmented lesion of her right nipple revealing mammary Paget disease and elucidate diagnostic obstacles and prognostic importance of early breast cancer detection.