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Breast Lumps


Mary Ann Kosir

, MD, Wayne State University School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020

A breast lump (mass) is a thickening or bump that feels different from surrounding breast tissue. A lump may be discovered in a breast incidentally, during a breast self-examination, or during a routine physical examination by a doctor.

(See also Overview of Breast Disorders.)

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 difficult.

Lumps may be painless or painful. They are sometimes accompanied by nipple discharge 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) or solid masses, which are usually fibroadenomas. Fibroadenomas are not cancerous, and cysts usually are not cancerous.

Causes of Breast Lumps

Common causes of breast lumps

The most common causes include

  • Fibroadenomas
  • Fibrocystic changes

Fibroadenomas 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 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.

Fibrocystic changes do not increase the risk of breast cancer.

Other causes of breast lumps

Lumps sometimes result from

  • Breast infections, including collections of pus (abscesses), which are very rare except during the few weeks after childbirth
  • A clogged milk gland (galactocele), which usually occurs up to 6 to 10 months after breastfeeding stops
  • Injuries, which can result in the formation of scar tissue
  • Breast cancer

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
  • Lymph nodes in the armpit that are matted together or stuck to the skin or chest wall
  • A bloody discharge from the nipple
  • Thickened, red skin over the breast

When to see a doctor

Because breast lumps may be cancerous (although they seldom are), they should be evaluated by a doctor within about 3 to 7 days.

Delay of a week or so is not harmful unless there are signs of infection such as redness, swelling, and/or a discharge of pus. Women with such symptoms should see a doctor within 1 or 2 days.

What the doctor does

Doctors ask the 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 and general symptoms such as weight loss, fatigue, and bone pain (which may indicate advanced cancer). Doctors ask the woman about her medical and family history, including a previous diagnosis of breast cancer and risk factors for breast cancer.

Doctors then do a physical examination, focusing on the breasts and areas near it (see 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 the 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.


Usually, testing is needed because determining whether breast lumps are cancerous or not during a physical examination is difficult and because failing to identify cancer has serious consequences.

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 is often inserted into the cyst, and the fluid is 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, the 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).

If the lump appears to be solid, mammography is typically done, followed by a biopsy. Doctors may do one of several types of 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 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 the 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, the woman should have regular check-ups so that her doctor can check for changes.

Treatment of breast cancer, if diagnosed, usually consists of surgery to remove the tumor plus radiation therapy, chemotherapy, and/or hormonal drugs.

Key Points about Breast Lumps

  • Most breast lumps are not cancer.
  • Because noncancerous and cancerous lumps are hard to tell apart during an examination, testing is usually done.

Drugs Mentioned In This Article

Generic Name Select Brand Names
acetaminophen TYLENOL

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