Fibroadenoma of the breast is a benign tumor. Benign tumor means it is not a cancer.
The cause of fibroadenomas is not known. They may be related to hormones. Girls who are going through puberty and women who are pregnant are most often affected. Fibroadenomas are found much less often in older women who have gone through menopause.
Fibroadenoma is the most common benign tumor of the breast. It is the most common breast tumor in women under age 30.
A fibroadenoma is made up of breast gland tissue and tissue that helps support the breast gland tissue.
Fibroadenomas are usually single lumps. Some women have several lumps that may affect both breasts.
The lumps may be any of the following:
- Easily moveable under the skin
The lumps have smooth, well-defined borders. They may grow in size, especially during pregnancy. Fibroadenomas often get smaller after menopause (if a woman is not taking hormone therapy).
Exams and Tests
After a physical exam, one or both of the following tests are usually done:
A biopsy may be done to get a definite diagnosis. Different types of biopsies include:
- Excisional (removal of the lump by a surgeon)
- Stereotactic (needle biopsy using a machine like a mammogram)
- Ultrasound-guided (needle biopsy using ultrasound)
Women in their teens or early 20s may not need a biopsy if the lump goes away on its own or if the lump does not change over a long period.
If a needle biopsy shows that the lump is a fibroadenoma, the lump may be left in place or removed.
You and your health care provider can discuss whether or not to remove the lump. Reasons to have it removed include:
- Results of needle biopsy are not clear
- Pain or other symptom
- Concern about cancer
- The lump gets larger over time
If the lump is not removed, your provider will watch to see if it changes or grows. This may be done using:
- Physical examination
Sometimes, the lump is destroyed without removing it:
- Cryoablation destroys the lump by freezing it. A probe is inserted through the skin, and ultrasound helps the provider guide it to the lump. Gas is used to freeze and destroy the lump.
- Radiofrequency ablation destroys the lump using high-frequency energy. The provider uses ultrasound to help focus the energy beam on the lump. These waves heat the lump and destroy it without affecting nearby tissues.
If the lump is left in place and watched carefully, it may need to be removed at a later time if it changes or grows.
In very rare cases, the lump is cancer, and will need further treatment.
When to Contact a Medical Professional
Call your provider if you notice:
- Any new breast lumps
- A breast lump that your provider has checked before that grows or changes
- Bruising on your breast for no reason
- Dimpled or wrinkled skin (like an orange) on your breast
- Nipple changes or nipple discharge
Breast lump - fibroadenoma; Breast lump - noncancerous; Breast lump - benign
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Gilmore RC, Lange JR. Benign breast disease. In: Cameron AM, Cameron JL, eds. Current Surgical Therapy. 13th ed. Philadelphia, PA: Elsevier; 2020:657-660.
Hacker NF, Friedlander ML. Breast disease: a gynecologic perspective. In: Hacker NF, Gambone JC, Hobel CJ, eds. Hacker and Moore's Essentials of Obstetrics and Gynecology. 6th ed. Philadelphia, PA: Elsevier; 2016:chap 30.
Smith RP. Breast fibroadenoma. In: Smith RP, ed. Netter's Obstetrics and Gynecology. 3rd ed. Philadelphia, PA: Elsevier; 2018:chap 166.
Review Date 3/5/2020
Updated by: Debra G. Wechter, MD, FACS, general surgery practice specializing in breast cancer, Virginia Mason Medical Center, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.