Fibroadenoma of the breast is a benign (noncancerous) tumor.

Fibroadenoma is the most common benign tumor of the breast and the most common breast tumor in women under age 30. Fibroadenomas are usually found as single lumps, but about 10-15% of women have several lumps that may affect both breasts.

Black women tend to develop fibroadenomas more often and at an earlier age than white women. The cause of fibroadenoma is not known.

Lumps may be:

• Firm
• Moveable
• Painless
• Rubbery

They should have well-defined borders, but they may grow in size, especially during pregnancy. The lumps often get smaller after menopause (if a woman is not taking hormones).

The following tests may be performed to gain information about a breast lump:

• Biopsy (needle or open)
• Breast ultrasound
• Fine needle aspiration
• Mammogram
• Physical examination

A biopsy is needed to get a firm diagnosis. Women in their teens or early 20s may not need a biopsy if the lump goes away on its own.

If a biopsy indicates that the lump is a fibroadenoma, the lump may be left in place or removed, depending on the patient and the lump. If left in place, it may be watched over time with:

• Mammograms
• Physical examinations
• Ultrasounds

The lump may be surgically removed at the time of an open biopsy (this is called an excisional biopsy). The decision depends on the features of the lump and the patient's preferences.

Alternative treatments include removing the lump with a needle and destroying the lump without removing it (such as by freezing, in a process called cryoablation).

The outlook is excellent, although patients with fibroadenoma have a slightly higher risk of breast cancer later. Lumps that are not removed should be checked regularly by physical exams and imaging tests, following the doctor's recommendations.

• Biopsy or removal may result in bleeding or scarring.
• Cancer may be found in the lump (very rare) and require further treatment.
• If the lump is left in place for observation, it may need to be removed at a later time if the lump changes, grows, or doesn't go away.

Call your health care provider if:

• A known lump changes
• You feel a new breast lump
• You note changes in the breast that aren’t affected by the menstrual cycle

Perform regular breast self-exams and undergo breast screening as recommended by your health care provider.