Causes
- Physiologic (Benign) Nipple Discharge – Most Common (97%)
- Pregnancy
- Lactation
- Postpartum Galactorrhea
- Spontaneous Abortion
- Fibrocystic Change
- Hormonal Fluctuations with Menstrual Cycle
- Prolactinoma (Pituitary Tumor)
- Endocrinopathies that Increase Prolactin Levels
- Medication Side Effects
- Pathologic Nipple Discharge
- Mastitis/Abscess
- Ductal Ectasia
- Intraductal Papilloma – Most Common Cause of Pathologic Nipple Discharge (52-57%)
- Neoplasia
“Pathologic” Discharge Factors
- Physiologic Factors:
- Bilateral
- Expressed
- Small Amount
- Multiple Ducts
- White, Milky or Clear
- Can Also Be Yellow (Straw Colored), Brown or Green
- Pathologic Factors:
- Unilateral
- Spontaneous
- Copious in Amount
- Single Duct
- Bloody or Serous (Clear or Yellow)
Substances
- White/Milky – Galactorrhea
- Brown, Yellow or Green – Often Caused by Fibrocystic Change
- Bloody – Caused by Intraductal Papilloma (Most Common) or Ductal Cancers
- Serous – Concerning for Cancer
Diagnostic Evaluation
- Physiologic Discharge: Reassurance
- Consider Galactorrhea Work Up (Pregnancy Test, Prolactin Level & Thyroid Function Tests)
- Pathologic Discharge: Imaging
- Initial Imaging: Bilateral Diagnostic Mammogram & US
- If Initial Imaging Negative: MRI
- Could Also Consider Galactography/Ductogram
- Other Considerations:
- Cytology is Not Useful
- Biopsy & Surgical Intervention as Indicated