Nipple Discharge Without a Dominant Mass from the NCCN

In patients with a nipple discharge but no dominant mass, an evaluation of the character of the nipple discharge is the first step. If the nipple discharge is bilateral and milky, then pregnancy or an endocrine etiology must be considered. The appropriate follow-up of a nonspontaneous, multiple-duct discharge in women under age 40 is observation, coupled with education of the patient to stop compression of the breast and to report any spontaneous discharge, if appropriate. In women aged 40 years or older, screening mammography and a further workup based upon the Final Assessment category along with education similar to that for younger women is recommended.

The most worrisome nipple discharge is one that is persistent, spontaneous, unilateral, and from a single nipple duct, especially if the discharge is serous, sanguinous, or serosanguinous. A guaiac test and cytology of the nipple discharge are optional, as a negative result should not stop further evaluation. Evaluation of this type of nipple discharge is based on the Final Assessment category of the diagnostic mammogram. If the diagnostic mammogram is Final Assessment category 1, 2, or 3, then a ductogram is preferred to guide the surgical excision. Ductal excision is indicated for diagnosis of an abnormal nipple discharge, even if the ductogram is negative. However, the ductogram is useful to exclude multiple lesions and to localize the lesions prior to surgery. If the patient has a mammogram that is a Final Assessment category 4 or 5, then the workup should proceed based on the diagnostic mammogram findings. If the workup findings are negative, a ductogram is preferred, but surgical duct excision would still be necessary. If the workup of a category 4 or 5 mammogram is positive, the patient should be treated according to the NCCN Breast Cancer Treatment Guidelines