Evaluation of nipple discharge
Nipple discharge is triaged by laterality, duct number, and character: bilateral milky discharge from multiple ducts points to a physiologic or endocrine cause and starts with a pregnancy test, TSH, and prolactin, while unilateral, single-duct, bloody or serous discharge is treated as possible ductal pathology and worked up with age-based breast imaging.
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What this article covers
- Overview
Nipple discharge is triaged, not treated as one disease: the history and exam sort every case into a bilateral/multiduct/milky pattern (usually physiologic or endocrine) versus a…
- Epidemiology
Nipple discharge is a common gynecologic complaint across the reproductive and perimenopausal age range.
- Risk factors
Age at presentation: advancing age raises the probability that unilateral discharge is malignant rather than papilloma or fibrocystic change.
- Pathophysiology
Bilateral milky discharge (galactorrhea) is driven by hyperprolactinemia: elevated prolactin stimulates alveolar milk secretion independent of pregnancy or breastfeeding.
- Clinical features
Character of the discharge is the dominant clue: bilateral discharge that is milky, clear, gray, yellow, brown, or green is more likely benign (physiologic, medication, mammary duct ectasia)…
- Differential diagnosis
Prolactinoma/hyperprolactinemia: bilateral milky galactorrhea with menstrual irregularity, headache, or bitemporal hemianopia; discriminated by an elevated prolactin level and pituitary MRI.
- Diagnosis
First, the diagnosis is the branch itself: bilateral/multiduct/nonbloody discharge is confirmed as physiologic or endocrine by pregnancy test, TSH, and prolactin, while unilateral/single-duct/bloody…
- Management
First, treat the underlying cause identified on workup, not the discharge itself; no empiric drug is given before the branch (endocrine versus ductal) is established.
- Complications
Delayed diagnosis of breast cancer if unilateral bloody discharge is misclassified as benign and imaging or biopsy is deferred.
- Prognosis
The large majority of nipple discharge is benign, particularly bilateral, multiduct, nonbloody discharge found to be physiologic, medication-related, or a treatable endocrine cause.
- Prevention
There is no primary prevention for nipple discharge itself; the preventable harm is delayed recognition of its cause, so prevention means adherence to the age-based diagnostic pathway.
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Related articles
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Intraductal papilloma is a benign papillary tumor of a single lactiferous duct beneath the areola and is the most common cause of unilateral bloody or serosanguinous nipple discharge in the nonlactating patient, confirmed by age-based breast imaging plus core needle biopsy and treated with surgical excision of the involved duct because of an associated risk of atypia or ductal carcinoma in situ.
- Prolactinoma
Prolactinoma is a prolactin-secreting pituitary adenoma, the most common functional pituitary tumor, presenting with hypogonadism and galactorrhea from prolactin excess or with headache and visual loss from mass effect in larger tumors. Diagnosis requires an elevated prolactin with a pituitary mass on dedicated MRI after excluding pregnancy, medication effect, and hypothyroidism, and first-line treatment is a dopamine agonist, most often cabergoline, which lowers prolactin and shrinks the tumor without surgery in most patients.
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