Nipple discharge.

A milky discharge may be of a benign endocrine nature, drug induced or secondary to a pituitary lesion. A clear or bloody discharge may be functional or related to benign or malignant breast lesions. Carcinoma is a very unusual cause of nipple discharge in the absence of a palpable mass or an abnormal mammogram. A unilateral bloody discharge without evidence of a tumor may stem from a benign intraductal papilloma. Careful follow-up evaluations are sufficient for a persistent nipple discharge, after serious pituitary and breast disorders have been ruled out.