Fibroadenomas of the Breast: Causes, Symptoms, and Treatment
A fibroadenoma is a breast lump. The term fibroadenoma combines the words “fibroma,” meaning a tumor made up of fibrous tissue, and “adenoma,” a benign growth of gland tissue.
A fibroadenoma typically has a well-defined round or oval shape. It may feel rubbery or hard, like a marble. It can also be flat, like a coin. When you touch it, it’s easy to move around under the skin as opposed to being stuck in one place.
Over time, a fibroadenoma may grow in size or even shrink and disappear. The average fibroadenoma is anywhere from the size of a small marble to a ping pong ball.
Types of fibroadenoma
There are four types of fibroadenomas:
Simple fibroadenomas are the most common type. They tend to be smaller, and the cells look the same throughout the tissue.
Complex fibroadenomas are more common in people older than 35. They tend to be larger and may have calcifications or cysts in them.
Giant fibroadenomas are bigger than 5 centimeters (about 2 inches).
Juvenile fibroadenomas are rare and develop in children and teens between the ages of 10 and 18.
Causes of fibroadenoma
Experts aren’t sure what causes fibroadenomas to develop, but believe estrogen plays a role. Breast tissue is known to be sensitive to estrogen. Fibroadenomas tend to grow during pregnancy, when estrogen levels are higher. They tend to shrink during menopause, when estrogen levels are lower. There may also be genetic causes.
Although anyone who has a period can develop a fibroadenoma, they are more likely to develop in people between the ages of 15 and 35. Black people have a slightly higher risk of developing a fibroadenoma.
It’s extremely rare, but men can also get fibroadenomas.
Symptoms of breast fibroadenoma
A fibroadenoma is typically painless, but it may be tender before you get your period. Large fibroadenomas can sometimes hurt when touched.
Diagnosing breast fibroadenoma
If you or your doctor feels a breast lump, your doctor first does a physical exam and asks about your medical history.
If you’re younger than 30, your doctor will likely examine the fibroadenoma with ultrasound.
If you're older than 35, your doctor will likely use both an ultrasound and a mammogram to look at the fibroadenoma.
No matter your age, your doctor also may do a biopsy to look at the type of cells in the fibroadenoma.
Fibroadenoma treatment
Fibroadenomas usually don’t require treatment unless they are large, painful, or growing rapidly. They often go away on their own. Your doctor may recommend monitoring the fibroadenoma for changes for a certain amount of time.
But if the fibroadenoma is large, it’s usually removed with surgery called an excisional biopsy. It’s typically an outpatient procedure, so you can go home the same day. After you’re given general anesthesia to put you to sleep, the surgeon will use a scalpel to remove the entire fibroadenoma. The incision is then stitched up. It may leave a scar, but you can usually return to your normal activities within a week or two.
Even if the fibroadenoma is small, your doctor may recommend a vacuum-assisted excision biopsy. With this procedure, you’re awake, and an injection of local anesthesia is used to numb the breast. Guided by ultrasound or other imaging, the surgeon or radiologist places a probe into the breast, and a vacuum draws the fibroadenoma into the probe.
Alternatively, the fibroadenoma can be frozen and destroyed in a procedure called cryoablation. Cryoablation is less common than surgery.
Fibroadenoma FAQ
Where are fibroadenomas usually located?
Fibroadenomas are most often found in the upper, outer part of the breast.
Can fibroadenomas turn into cancer?
Most fibroadenomas don’t increase breast cancer risk. Complex fibroadenomas, which are very uncommon, slightly increase your risk of breast cancer compared to someone with no breast lumps.
What happens if fibroadenoma is left untreated?
Often fibroadenomas do not require treatment and will go away on their own. However, some will grow slowly and may begin to cause discomfort.
Can you get fibroadenomas more than once?
Yes. You can get more than one fibroadenoma. This is why it’s so important to know how your breasts feel and tell your doctor about any new lumps you find.
