Breast disorders may be noncancerous (benign) or cancerous (malignant). Most are noncancerous and not life threatening. Often, they do not require treatment. In contrast, breast cancer can mean loss of a breast or of life. Thus, for many women, breast cancer is their worst fear. However, potential problems can be detected early when women regularly examine their breasts themselves, are examined regularly by their doctor, and have mammograms as recommended. Early detection of breast cancer is essential to successful treatment.

Symptoms

Symptoms related to the breast are common. They include breast pain, lumps, and a discharge from the nipple. The breast's skin may become pitted, puckered, or dimpled. Breast symptoms do not necessarily mean that a woman has breast cancer or another serious disorder. For example, monthly breast tenderness that is related to hormonal changes before a menstrual period does not indicate a serious disorder. However, women should examine their breasts once a month (see Breast Disorders: How to Do a Breast Self-Examination) and should see their doctor if they observe any change in a breast, particularly any of the following:

Inside the Breast The female breast is composed of milk-producing glands (lobules) surrounded by fatty tissue and some connective tissue. Milk secreted by the glands flows through ducts to the nipple. Around the nipple is an area of pigmented skin called the areola.

• A lump that feels distinctly different from other breast tissue or that does not go away
• Swelling that does not go away
• Pitting, puckering, or dimpling in the skin of the breast
• Scaly skin around the nipple
• Changes in the shape of the breast
• Changes in the nipple, such as turning inward
• Discharge from the nipple, especially if it is bloody

Breast Pain: Many women experience breast pain (mastalgia). Causes include the following:

• Hormonal changes
• Cysts
• Infection
• Fibrocystic changes
• Very rarely, cancer

Breast pain may be related to hormonal changes. For example, it may occur during or just before a menstrual period (as part of the premenstrual syndrome) or early in pregnancy. Women who take oral contraceptives or who take hormone therapy after menopause commonly have this kind of pain. When levels of the female hormones estrogen and progesterone increase (during the menstrual cycle or pregnancy or because of therapy), they cause the milk glands and ducts of the breasts to enlarge and the breasts to retain fluid. The breasts then become swollen and sometimes painful. Such pain is usually diffuse, making the breasts tender to touch. Pain related to the menstrual period may come and go for months or years.

Other causes of breast pain include breast cysts, infections, and abscesses. In these cases, breast pain is usually felt in a particular place. Fibrocystic changes (formerly called fibrocystic breast disease) may include breast pain. Pain is the first symptom in only about 5% of women with breast cancer. Breast pain that persists for more than 1 month should be evaluated.

Mild breast pain usually disappears eventually, even without treatment. Pain that occurs during menstrual periods can usually be relieved by taking acetaminophen or a nonsteroidal anti-inflammatory drug (NSAID).

For certain types of severe pain, danazol (a synthetic hormone related to testosterone) or tamoxifen (a drug used to treat breast cancer) may be used. These drugs inhibit the activity of estrogen and progesterone, which can make the breasts swell and be painful. Because long-term use of these drugs has side effects, the drugs are usually given for only a short time. Tamoxifen has fewer side effects than danazol. Tamoxifen is used mainly in postmenopausal women but may benefit younger women.

If a specific disorder is identified as the cause, the disorder is treated. For example, if a cyst is the cause, draining the fluid from the cyst usually relieves the pain.

Breast Lumps: Lumps in the breasts are relatively common and are usually not cancerous. Causes include the following:

• Cysts
• Fibroadenomas
• Scar tissue
• Rarely cancer

But because lumps may be cancerous, they should be evaluated by a doctor without delay. Lumps may be fluid-filled sacs (cysts) or solid masses, which are usually fibroadenomas (see Breast Disorders: Fibroadenomas).

Other solid breast lumps include hardened glandular tissue (sclerosing adenosis) and scar tissue that has replaced injured fatty tissue (fat necrosis). Neither is cancerous. However, these lumps can be diagnosed only by biopsy. They require no treatment.

Nipple Discharge: One or both nipples sometimes discharge a fluid. A nipple discharge occurs normally during milk production (lactation) after childbirth. Or it can occur when the nipple is mechanically stimulated by fondling, suckling, or irritation from clothing or when women are sexually aroused. During the last weeks of pregnancy, the breasts may produce a milky discharge (colostrum). Stress can also result in a nipple discharge.

A normal nipple discharge is a thin, cloudy, whitish or almost clear fluid that is not sticky. However, during pregnancy or breastfeeding, a slightly bloody discharge sometimes occurs normally.

Several disorders can cause an abnormal discharge. Abnormal discharges vary in appearance depending on the cause:

• A bloody discharge may be caused by a noncancerous breast tumor (such as a tumor in a milk duct, called an intraductal papilloma) or, less commonly, by breast cancer. Among women who have an abnormal discharge, breast cancer is the cause in fewer than 10%.
• A greenish discharge is usually due to a fibroadenoma, which is a noncancerous solid lump.
• A discharge that contains pus and smells foul may result from a breast infection.
• A large amount of milky discharge in women who are not breastfeeding may represent galactorrhea (see Pituitary Gland Disorders: Galactorrhea).

Disorders of the pituitary gland or brain, encephalitis (a brain infection), an underactive thyroid gland (hypothyroidism), kidney or liver disorders, and head or chest injuries can also cause a nipple discharge.

Taking certain drugs can cause a nipple discharge. These drugs include opioids, certain drugs used to treat stomach disorders (such as cimetidine, ranitidine, and metoclopramide), certain antidepressants, and certain antihypertensives (such as methyldopa, reserpine, and verapamil).

PrintOpen table
What Causes Nipple Discharge? Type Examples Breast disorders Breast cancer Breast infections or abscesses Fibrocystic changes Most commonly, noncancerous milk duct tumors (intraductal papilloma) Other disorders Brain disorders Encephalitis (a brain infection) Head or chest injuries Kidney disorders Liver disorders Pituitary gland disorders An underactive thyroid gland (hypothyroidism) Drugs Certain antidepressants Certain antihypertensives, such as methyldopa, reserpine, and verapamil Older antipsychotic drugs such as chlorpromazine Certain drugs used to treat stomach disorders, such as cimetidine, ranitidine, and metoclopramide Opioids Oral contraceptives

A discharge from one breast is likely to be caused by a problem with that breast, such as a noncancerous or cancerous breast tumor. A discharge from both breasts is more likely to be caused by a problem outside the breast, such as a hormonal disorder or use of certain drugs.

If a nipple discharge persists for more than one menstrual cycle or seems unusual, women should see a doctor. Postmenopausal women who have a nipple discharge should see a doctor promptly. Doctors examine the breast, looking for abnormalities. Tests that may be done include ultrasonography of the breast, mammography, blood tests to measure hormone levels, and computed tomography (CT) or magnetic resonance imaging (MRI) of the head. Women are asked for a complete list of drugs they are taking. Sometimes a specific cause cannot be identified.

If a disorder is the cause, the disorder is treated. If a noncancerous tumor is causing a discharge from one breast, the duct that the discharge is coming from may be removed.

Last full review/revision November 2008 by Victor G. Vogel, MD, MHS