The authors report 46 cases of nipple discharge without any palpable lesion. The diagnostic is made, most of the time, by 3-views bilateral mammograms. The place of other examinations (ultrasonography, galactography) is reported. The cytology of the discharge, as well as its macroscopic appearance (bloody, serous or greenish), determine the surgical indications. Quadrantectomy centered around the discharging duct, is the procedure of choice in this disease, at the interface between diagnostic and treatment, in fact, if benign tumors (papillomas) or non tumoral diseases (fibrocystic mastopathy and duct ectasia) predominate, invasive or in-situ malignant lesions represent 13 p. cent of these 46 discharges, justifying the significance of this clinical sign.