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Breast Lumps


Mary Ann Kosir

, MD, Wayne State University School of Medicine

Reviewed/Revised Feb 2024
Topic Resources

A breast lump (mass) is a thickening or bump that feels different from surrounding breast tissue. A lump may be discovered by a woman or during a breast examination by a doctor.

Lumps in the breasts are relatively common and usually not cancerous.

Did You Know...

  • Most breast lumps are not cancer, but tests are needed because distinguishing noncancerous from cancerous lumps is important.

Lumps may be painless or painful. They are sometimes accompanied by a nipple discharge Nipple Discharge Fluid that leaks from one or both nipples is called nipple discharge. Each breast has several (15 to 20) milk ducts. A discharge can come from one or more of these ducts. (See also Overview... read more or changes in the skin, such as irregularities, redness, a dimpled texture (called peau d'orange, or skin of an orange), or tightened skin.

Breast lumps may be fluid-filled sacs (cysts Breast Cysts Breast cysts are fluid-filled sacs that develop in the breast. (See also Overview of Breast Disorders and Breast Lumps.) Breast cysts are common. In some women, cysts develop frequently, sometimes... read more ) or solid masses, which are usually fibroadenomas. Fibroadenomas are not cancerous, and cysts usually are not cancerous.

The Breasts

Causes of Breast Lumps

Common causes of breast lumps

The most common causes involve the fibroglandular tissue (composed of fibrous connective tissue and glands) in the breast, including

  • Fibroadenomas

  • Fibrocystic changes

Fibroadenomas Fibroadenomas of the Breast Fibroadenomas of the breast are small, smooth, solid, rounded noncancerous lumps composed of fibrous and glandular tissue. (See also Overview of Breast Disorders and Breast Lumps.) Fibroadenomas... read more are typically smooth, rounded, movable, painless lumps. They usually develop in women of child-bearing age, and they may decrease in size over time. Fibroadenomas may be mistaken for breast cancer, but they are not. Some types of fibroadenoma do not appear to increase the risk of breast cancer. Others may increase the risk slightly.

Fibrocystic changes Fibrocystic Changes of the Breast Fibrocystic changes of the breast (formerly called fibrocystic breast disease) include breast pain, cysts, and lumpiness that are not due to cancer. (See also Overview of Breast Disorders and... read more includes pain, cysts, and general lumpiness in the breast. Women may have one or more of these symptoms. Breasts feel lumpy and dense and are often tender when touched. These changes are more common among women who began to menstruate early, had their first baby after age 30, or have not had a baby.

In most women, fibrocystic changes are related to the monthly fluctuations in levels of the female hormones estrogen and progesterone. These hormones stimulate breast tissue. Symptoms tend to subside after menopause.

Fibrocystic changes do not increase the risk of breast cancer.

Other causes of breast lumps

Lumps sometimes result from

Infections, galactoceles, and scar tissue formation do not increase the risk of breast cancer.

Evaluation of Breast Lumps

Warning signs

Certain symptoms and characteristics are cause for concern:

  • A lump that is stuck to the skin or chest wall

  • A lump that is hard and irregular in texture

  • Dimpling of skin near the lump

  • Thickened, red skin over the breast

  • A bloody discharge from the nipple

  • Lymph nodes in the armpit that are matted together or stuck to the skin or chest wall

When to see a doctor

Because breast lumps may be cancerous (although they usually are not), they should be evaluated by a doctor as soon as possible.

What the doctor does

Doctors ask a woman questions about the lump, such as how long it has been present, whether it comes and goes, and whether it is painful. Doctors also ask about other symptoms, including any discharge from the nipple Nipple Discharge Fluid that leaks from one or both nipples is called nipple discharge. Each breast has several (15 to 20) milk ducts. A discharge can come from one or more of these ducts. (See also Overview... read more and general symptoms such as weight loss, fatigue, and bone pain. Doctors ask a woman about her medical and family history, including a previous diagnosis of breast cancer and risk factors for breast cancer Risk Factors for Breast Cancer Breast cancer occurs when cells in the breast become abnormal and divide into more cells uncontrollably. Breast cancer usually starts in the glands that produce milk (lobules) or the tubes ... read more Risk Factors for Breast Cancer .

Doctors then do a breast examination (see Screening Screening Breast cancer rarely causes symptoms in its early stages, and early treatment is more likely to be successful; thus, screening is important. Screening is the hunt for a disorder before any symptoms... read more Screening ). Doctors inspect the breast, looking for abnormalities, changes in the skin, and nipple discharge. They also feel (palpate) the lump to determine

  • How large it is

  • Whether it is hard or soft

  • Whether it is smooth or irregular

  • Whether it is painful

  • Whether it moves freely or is stuck to the skin or chest wall

Painful, rubbery lumps in younger women are usually fibrocystic changes, particularly if a woman has had similar lumps before.

Doctors determine whether the breasts are similar in shape and size and check each breast for abnormalities, particularly warning signs. Cancer is more likely if warning signs are present.

Doctors also feel the lymph nodes in the armpits and above the collarbone to check for enlarged or painful lymph nodes.


If a breast lump is found on breast examination, further testing is needed to determine whether it is cancerous.

Ultrasonography is typically done first to try to differentiate solid lumps from cysts, which are rarely cancerous.

If the lump appears to be a cyst and is causing symptoms (such as pain or nipple discharge), a needle with a syringe may be inserted into the cyst, and the fluid removed (called aspiration) and examined. The fluid is tested for cancer cells only if any of the following occurs:

  • It is bloody or cloudy.

  • Little fluid is obtained.

  • The lump remains after aspiration.

Otherwise, a woman is checked again in 4 to 8 weeks. If the cyst cannot be felt, it is considered noncancerous. If it recurs, aspiration is done again, and the fluid is sent for analysis regardless of appearance. If the cyst recurs a third time or if a lump is still present after it was aspirated, a sample of tissue from the lump or the entire lump is removed and examined under a microscope (biopsy).

  • Fine-needle aspiration biopsy: Some cells are removed from the lump through a thin needle attached to a syringe.

  • Core needle biopsy: A larger needle with a special tip is used to remove a larger sample of breast tissue.

  • Open (surgical) biopsy: Doctors make a small cut in the skin and breast tissue and remove part or all of a lump. This type of biopsy is done when a needle biopsy is not possible (for example, because no lump is felt). It may also be done after a needle biopsy that does not detect cancer to be sure that the needle biopsy did not miss a cancer.

Ultrasonography or mammography is often used to guide placement of the needle for the biopsy. Most women do not need to be hospitalized for these procedures. Usually, only a local anesthetic is needed.

Treatment of Breast Lumps

Treatment of breast lumps and fibrocystic changes depends on what the cause is and whether symptoms are present.

For fibrocystic changes, wearing a soft, supportive bra, such as an athletic bra, and taking pain relievers, such as acetaminophen or a nonsteroidal anti-inflammatory drug (NSAID), may help relieve symptoms.

Sometimes cysts are drained.

Fibroadenomas are usually removed if they are enlarging or causing pain or if a woman wants them to be removed. If the fibroadenomas are small, they may be destroyed using cold (cryoablation). Usually for this procedure, only a local anesthetic is required. However, after one fibroadenoma is removed, other fibroadenomas may appear in other parts of the breast. If several lumps have been removed and found to be noncancerous, a woman and her doctor may decide against removing new lumps that develop. Regardless of whether the fibroadenomas are removed or not, a woman should have regular check-ups so that her doctor can check for changes.

If a lump is a galactocele (a clogged milk gland), it is drained (aspirated). It typically resolves after this treatment.

Key Points

  • Most breast lumps are not cancer.

  • Women with a breast lump should see a health care professional, who examines the breast and usually does additional tests.

Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
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