Nipple discharge may arise from single or multiple ducts and be unilateral or bilateral. Causes are given in Table 10.2.
There may be a mass palpable, which when pressed produces the discharge. Even if no mass is palpable, the discharge may come from one duct when one segment of the breast is pressed. Lymph nodes should be looked for.
Any associated breast lump should be investigated. Unilateral blood-stained discharge is suggestive of an intraductal papilloma and also requires a triple assessment. Copious bilateral milky discharge (galatorrhoea) may indicate a prolactinoma hence a serum prolactin level should be sent.
If there is no mass, a non-bloody discharge and the investigations have proved negative, management is conservative. Surgical intervention is indicated if the discharge is profuse and embarrassing or if malignancy cannot be excluded. For management of specific causes see relevant conditions.