Clinical examination of the nipple is part of normal breast screening procedures. Abnormal processes of benign or malignant nature may be reflected by erythema, erosion, swelling or acquired inversion. In patients presenting with a persistent unilateral nipple lesion, it is advisable to collect a sample to exclude Paget's disease of the nipple, a rare form of ductal carcinoma in situ (DCIS). Imaging should be performed to detect breast cancer, which is found in more than 80% of cases, and determine its possible multifocal nature. Breast MRI is indicated if breast-conserving surgery is planned. The main differential diagnoses are erosive adenomatosis and eczema of the nipple. Acquired inverted nipple is generally of inflammatory origin. It is usually diagnosed by conventional breast examination but breast MRI can be helpful when in doubt about possible underlying neoplasia.