Nipple discharge is a common complaint in women who are not pregnant or breastfeeding, especially during the reproductive years. Nipple discharge is not necessarily abnormal, even among postmenopausal women, although it is always abnormal in men. Spontaneous unilateral nipple discharge, regardless of color, is considered abnormal.
Nipple discharge can be serous (yellow), mucinous (clear and watery), milky, sanguineous (bloody), purulent, multicolored and sticky, or serosanguineous (pink). It may occur spontaneously or only in response to breast manipulation.
Nipple discharge may be breast milk or an exudate produced by a number of conditions.
Breast milk production in nonpregnant and nonlactating women (galactorrhea Galactorrhea Galactorrhea is lactation in any men or in women who are not breastfeeding. It is generally due to a prolactin-secreting pituitary adenoma. Diagnosis is by measurement of prolactin levels and... read more ) typically involves an elevated level of prolactin, which stimulates glandular tissue of the breast. However, only some patients with elevated prolactin levels develop galactorrhea.
Most frequently, nipple discharge has a benign cause (see table Some Causes of Nipple Discharge Some Causes of Nipple Discharge Nipple discharge is a common complaint in women who are not pregnant or breastfeeding, especially during the reproductive years. Nipple discharge is not necessarily abnormal, even among postmenopausal... read more ). Cancer (usually intraductal carcinoma or invasive ductal carcinoma) causes < 10% of cases. The rest result from benign ductal disorders (eg, intraductal papilloma, mammary duct ectasia, fibrocystic changes Etiology The term breast mass is preferred over lump for a palpably discrete area of any size. A breast mass may be discovered by patients incidentally or during breast self-examination or by the clinician... read more ), endocrine disorders (eg, pituitary tumor, hypothyroidism), liver disorders, breast abscesses or infections, or use of certain drugs. Of these causes, intraductal papilloma is probably the most common; it is also the most common cause of a bloody nipple discharge without a breast mass.
Endocrine causes involve elevation of prolactin levels, which has numerous causes.
History of present illness should include the following:
Whether the current discharge is unilateral or bilateral
What its color is
How long it has lasted
Whether it is spontaneous or occurs only with nipple stimulation
Whether a mass Breast Masses (Breast Lumps) The term breast mass is preferred over lump for a palpably discrete area of any size. A breast mass may be discovered by patients incidentally or during breast self-examination or by the clinician... read more or breast pain Mastalgia (Breast Pain) Mastalgia (breast pain) is common and can be localized or diffuse and unilateral or bilateral. Localized breast pain is usually caused by a focal disorder that causes a mass, such as a breast... read more is present
Review of systems should seek symptoms suggesting possible causes, including the following:
Amenorrhea, infertility, headache, or visual disturbances: Pituitary tumor Pituitary Lesions Patients with hypothalamic-pituitary lesions generally present with some combination of Symptoms and signs of a mass lesion: headaches, altered appetite, thirst, visual field defects—particularly... read more
Ascites Ascites Ascites is free fluid in the peritoneal cavity. The most common cause is portal hypertension. Symptoms usually result from abdominal distention. Diagnosis is based on physical examination and... read more or jaundice Jaundice Jaundice is a yellowish discoloration of the skin and mucous membranes caused by hyperbilirubinemia. Jaundice becomes visible when the bilirubin level is about 2 to 3 mg/dL (34 to 51 micromol/L)... read more : Liver disorders
Past medical history should include possible causes of hyperprolactinemia, including chronic renal failure, pregnancy, liver disorders, and thyroid disorders, as well as history of infertility, hypertension, depression, breastfeeding, menstrual patterns, and cancer. Clinicians should ask specifically about drugs that can cause prolactin release such as oral contraceptives, antihypertensive drugs (eg, methyldopa, reserpine, verapamil), H2-antagonists (eg, cimetidine, ranitidine), opioids, and dopamine D2 antagonists (eg, many psychoactive drugs, including phenothiazines and tricyclic antidepressants).
Physical examination focuses on the breasts. The breasts are inspected for symmetry, dimpling of the skin, erythema, swelling, color changes in the nipple and skin, and crusting, ulceration, or retraction of the nipple. The breasts are palpated for masses and evidence of lymphadenopathy in the axillary or supraclavicular region. If there is no spontaneous discharge, the area around the nipples is systematically palpated to try to stimulate a discharge and to identify any particular location associated with the discharge.
A bright light and magnifying lens can help assess whether the nipple discharge is uniductal or multiductal.
Important differentiating points are
If a mass is present, cancer must be considered. Because cancer rarely involves both breasts or multiple ducts at presentation, a bilateral, guaiac-negative discharge suggests an endocrine cause. However, if the discharge is guaiac-positive, even if bilateral, cancer must be considered.
Presence of any of the following requires follow-up with a surgeon who is experienced with breast disorders:
For other suggestive findings, see table Some Causes of Nipple Discharge Some Causes of Nipple Discharge Nipple discharge is a common complaint in women who are not pregnant or breastfeeding, especially during the reproductive years. Nipple discharge is not necessarily abnormal, even among postmenopausal... read more .
If endocrine causes are suspected, the following are measured:
If discharge is guaiac-positive, the following is done:
If there is a palpable mass, evaluation as for breast mass is done, usually beginning with
Lesions that appear cystic are sometimes aspirated, and solid masses or any that remain after aspiration are evaluated with mammography followed by imaging-guided biopsy.
If there is no mass but cancer is otherwise suspected or if other tests are indeterminate, the following is done:
Abnormal results are evaluated by biopsy-guided imaging. If mammography and ultrasonography do not identify a source and the discharge is spontaneous and comes from a single duct or breast, ductography (contrast-enhanced imaging of the milk duct) can be done.
Nipple discharge is most often benign.
Bilateral, multiductal, guaiac-negative discharge is usually benign and has an endocrine etiology.
Spontaneous, unilateral discharge requires diagnostic testing; this type of discharge may be cancer, particularly if it is bloody (or guaiac-positive).
Presence of a breast mass, a bloody (or guaiac-positive) discharge, or history of an abnormality on a mammogram or an ultrasound scan requires follow-up with a surgeon who is experienced with breast disorders.