Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Fibrocystic Changes of the Breast


Mary Ann Kosir

, MD, Wayne State University School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020
Click here for the Professional Version
Topic Resources

Fibrocystic changes of the breast (formerly called fibrocystic breast disease) include breast pain, cysts, and lumpiness that are not due to cancer.

Most women have some general lumpiness in the breasts, usually in the upper outer part, near the armpit. Many women have this kind of lumpiness, breast pain, breast cysts, or some combination of these symptoms—a condition called fibrocystic changes.

Normally, the levels of the female hormones estrogen and progesterone fluctuate during the menstrual cycle. Milk glands and ducts enlarge and breasts retain fluid when levels increase, and the breasts return to normal when levels decrease. (These fluctuations partly explain why breasts are swollen and more sensitive during a particular time of each menstrual cycle.) Fibrocystic changes may result from repeated stimulation by these hormones.

The following increase the risk of fibrocystic changes, possibly because they involve longer exposure to estrogen:

  • Starting to menstruate at an early age

  • Having a first baby at age 30 or later

  • Never having a baby

Other breast disorders, such as breast infections, can cause fibrocystic changes.

The lumpy areas may enlarge, causing a feeling of heaviness, discomfort, tenderness to the touch, or a burning pain. The symptoms tend to subside after menopause.

Fibrocystic changes do not increase the risk of breast cancer.

Diagnosis of Fibrocystic Breast Changes

  • Biopsy

Typically, a sample of tissue from an area that appears abnormal or different from other areas must be removed and examined under a microscope (biopsy) to rule out cancer. Sometimes the sample can be removed with a needle, but sometimes it must be removed surgically.

Fibrocystic changes may make the breasts appear dense on mammograms and thus may make breast cancer more difficult to detect.

Treatment of Fibrocystic Breast Changes

  • Sometimes removal of a lump

  • Sometimes drugs to relieve symptoms

If there is only one lump or if one lump appears to be different from other lumps, the lump may be removed.

No specific treatment is available or required for fibrocystic changes, but certain measures may help relieve symptoms:

  • Wearing a soft, supportive bra, such as an athletic bra

  • Taking pain relievers such as acetaminophen

Sometimes cysts are drained, but they may recur.

If symptoms are severe, doctors may prescribe drugs, such as danazol (a synthetic male hormone) or tamoxifen (which blocks the effects of estrogen). Because side effects can occur with long-term use, the drugs are usually given for only a short time. Tamoxifen has fewer side effects than danazol.

Drugs Mentioned In This Article

Generic Name Select Brand Names
No US brand name
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Test your knowledge

Postpartum Infections of the Uterus
Maternal infections that develop after the delivery of a baby usually begin in the uterus. The likelihood of developing a uterine infection is increased with which of the following types of delivery?
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID