A fibroadenoma is a benign, or noncancerous, breast tumor. Unlike a breast cancer, which grows larger over time and can spread to other organs, a fibroadenoma remains in the breast tissue.
They’re pretty small, too. Most are only 1 or 2 centimeters in size. It’s very rare for them to get larger than 5 centimeters across.
Usually, a fibroadenoma won’t cause any pain. It will feel like a marble that moves around beneath your skin. You may describe the texture as firm, smooth, or rubbery. In some cases, though, you won’t even be able to feel it at all.
What Are the Symptoms of Fibroadenomas?
Since they’re usually painless, you might not notice one until you feel a lump while you’re in the shower or during a self breast exam.
Other times, a doctor might find it on a mammogram or ultrasound.
Unlike breast cancer, a fibroadenoma doesn’t cause nipple discharge, swelling, redness, or skin irritation around the breast.
What Causes Fibroadenomas?
Scientist don’t know what causes them. They may be related to changing levels of hormones, since they often appear during puberty or pregnancy and go away after menopause.
How is a fibroadenoma different from a cancerous lump?
Fibroadenomas are generally asymptomatic and hence usually discovered on routine examination by self or the doctor. Common clinical features of fibroadenomas are:
- Fibroadenomas are painless
- They are usually small, between one and two centimeters
- They are round with smooth edges
- The lump is mobile and can be moved around within the breast tissue. Hence, fibroadenomas are also called “breast mice.”
- It feels firm (similar to the tip of the nose) and rubbery.
- Multiple lumps may be seen in one or both breasts.
- It is slow growing.
- Size may increase during pregnancy, hormonal therapy, or breastfeeding (breastfeeding is not affected).
- Larger fibroadenomas may cause breast asymmetry, causing aesthetic concerns.
|Seen in premenopausal women||Seen in postmenopausal women|
|Feels round, firm, rubbery with smooth edges||Feels hard with parts of firm areas|
|Typically painlessl||Painless in the early stages. Pain may develop in the later stages due to complications|
|Freely mobile within the breast||Usually fixed to underlying breast tissue or skin, hence not mobile|
|Skin over the lump is normal and not involved||Skin involvement leads to puckering and redness of the skin, giving an orange peel appearance|
|Nipple is not involved||Nipple may be involved, causing change in the shape of the nipple. Usually appears pulled in. nipple discharge and bleeding may be present|
|Usually slow glowing||Fast growing and can spread to other organ systems|
|Can be managed conservatively using a “wait and watch” approach||Requires urgent medical and surgical care|
What Are the Types of Fibroadenomas?
There are a few different kinds:
- Simple fibroadenomas. They look the same all over when you view them under a microscope.
- Complex fibroadenomas. These are bigger and tend to affect older women. They might have cells that grow rapidly.
- Juvenile fibroadenomas. These are the most common type of breast lump found in girls and adolescents between the ages of 10 and 18. They can grow large, but most shrink over time. Some disappear.
- Giant fibroadenomas. They can grow to larger than 2 inches. They may need to be removed if they press on or replace other breast tissue.
Who Gets Them?
Fibroadenomas are very common. About 10% of women have one of these breast lumps, often without ever knowing.
They most often appear in women between the ages of 15 and 35, or during pregnancy and breastfeeding. Some researchers have found that women with a family history of breast cancer are more likely to get fibroadenomas.
Most women only have one. But about 10% to 15% of women who get them have more than one, either at the same time or over time.
How Are Fibroadenomas Diagnosed?
If you find a lump in your breast, you should see your doctor. You can’t tell for sure what it is by how it feels.
Your doctor will likely feel the lump so they can gauge its texture and size. Even if they think it might be a fibroadenoma, they may recommend that you get more tests to confirm it.
You may get an ultrasound or a mammogram, depending on your age and whether you’re pregnant. Both are quick scans that you’ll get in the doctor’s office.
A radiologist will then check the images of your breast tissue to see if it’s a fibroadenoma or something else.
The only way for a doctor to know for sure that it’s a fibroadenoma is through a biopsy, which means taking a sample of the lump to test in a lab. Based on the results of your examination and scan, your doctor will decide whether they need to get extra confirmation from a biopsy. To do a biopsy, a doctor will insert a thin needle into your breast and pull out a small sample from the lump.
How Are Fibroadenomas Treated?
You might not need any treatment. If your fibroadenoma is small, your doctor may recommend simply waiting to see whether the lump grows or shrinks rather than trying to remove it right away.
Can fibroadenomas turn into breast cancer?
Although it is rare, complex fibroadenomas and phyllodes tumors have a chance to develop into malignant breast cancer. Hence, timely medical attention and management of the tumor are highly recommended.