What is a fibroadenoma?
A fibroadenoma is a noncancerous (benign) breast lump. This smooth, round, solid tumor consists of fibrous tissue and glandular tissue that form a mass. In very rare cases, a fibroadenoma may contain breast cancer.
Fibroadenomas often shrink or go away without treatment. Your healthcare provider may watch a fibroadenoma over time to see how it changes or recommend surgery to remove it.
What are the types of fibroadenomas?
There are two main types of fibroadenomas:
- Simple fibroadenomas are the most common. They tend to be smaller. These lumps don’t increase your breast cancer risk. Under a microscope, the biopsied tissue appears uniform (the cells look the same all over).
- Complex fibroadenomas are more common in people older than 35 and tend to be larger. Under a microscope, your provider may find some differences in the cells (they’re not uniform like a simple fibroadenoma). Your provider may also see calcifications or cysts on your mammogram. They may increase your risk for breast cancer slightly when compared to that of people with no breast lumps. Complex fibroadenomas occur about 15% of the time.
Other types of fibroadenomas include:
- Giant fibroadenomas, which are fibroadenomas that grow to be larger than 5 centimeters (cm).
- Juvenile fibroadenoma, a fibroadenoma that occurs in children and teenagers between 10 and 18 years old. They’re rare.
How common are fibroadenomas?
Benign breast lumps, including fibroadenomas, are common. A fibroadenoma is the most common type of benign breast lump. They happen most often when you’re between 15 and 35 years old. Up to 10% of women and people assigned female at birth (AFAB) will have a fibroadenoma at some point in their lives.
Symptoms and Causes
What are the symptoms of fibroadenomas?
Fibroadenomas are solid lumps (not filled with fluid) in one or both breasts. They aren’t painful and move easily under your skin if you push them around your breast. They can be as small as a pea or grow as large as a golf ball (about 2 to 3 cm is typical).
A fibroadenoma can be:
- Round or oval with clear borders.
- Firm or rubbery.
You may notice it becomes tender in the few days just before the start of your period. Large fibroadenomas are more likely to cause pain than a small fibroadenoma.
Fibroadenomas tend to grow very slowly, but they don’t always get bigger and may even shrink. This is especially true if you’re in your teen years or have reached menopause. Conversely, a fibroadenoma may grow larger during pregnancy.
What causes fibroadenomas?
Healthcare providers don’t know why some people get fibroadenomas. Some believe it has to do with being sensitive to estrogen. This is because fibroadenomas tend to grow during pregnancy or hormone therapy (when estrogen is higher), while they’re more likely to shrink after menopause (when estrogen is lower).
Fibroadenomas grow in the lobule area of your breast tissue. Lobules are the glands in your breasts that make milk during lactation.
What are the risk factors for fibroadenoma?
Fibroadenoma is most common in women and people assigned female at birth between 15 and 35. However, anyone who has a period (menstruates) can get them. Once a person reaches menopause, they become uncommon. Black people have a slightly higher risk of developing a fibroadenoma.
What are the complications of fibroadenomas?
Most fibroadenomas aren’t life-threatening or cancerous. But, they can get bigger, change in appearance or become painful. Like most breast diseases, the best way to prevent complications is to get regular breast exams or mammograms. While breast disease is often unavoidable, your risk for complications from these diseases decreases with early detection.
Diagnosis and Tests
How is a fibroadenoma diagnosed?
Contact your healthcare provider anytime you notice a breast lump or breast changes. Some fibroadenomas are too small to notice. If you or your healthcare provider finds a lump, your provider may perform these tests to determine what type of lump you have:
- Imaging scans, including mammogram and ultrasound.
- Image-guided core needle breast biopsy. This test involves removing a sample of the fibroadenoma and sending it to a lab for analysis.
Management and Treatment
How are fibroadenomas managed or treated?
Some fibroadenomas shrink in size or disappear without treatment. If a biopsy confirms the lump isn’t cancerous, your healthcare provider may recommend follow-up appointments to monitor the lump for any changes (usually in three to six months). This could involve manual breast exams, ultrasound or mammogram.
Sometimes, a provider recommends surgery to remove a fibroadenoma. This happens when they’re concerned about the results of your imaging tests or biopsy, or if the lump causes pain. Surgery is sometimes necessary for very large fibroadenomas. The most common procedure to remove a fibroadenoma is a surgical excision (cutting the lump out). Another option involves freezing the fibroadenoma in a procedure called cryoablation. Healthcare providers don’t use this method as often.
Can I get fibroadenomas more than once?
Yes, it’s possible to get more than one fibroadenoma. That’s why it’s important to become familiar with how your breasts typically feel. You should alert your healthcare provider to any new lumps in your breasts.
Should fibroadenomas be removed?
Healthcare providers may recommend removing a fibroadenoma if it’s large, painful or suspicious. However, this isn’t always the case. Many fibroadenomas shrink or go away without treatment.
What happens if a fibroadenoma is left untreated?
In the case of a small, unsuspicious fibroadenoma, nothing happens if it goes untreated. Your healthcare provider is the best person to decide if removing a fibroadenoma is necessary or if monitoring it for changes is a better route. Be sure to ask your provider any questions you have so you understand your treatment plan.
How can I prevent fibroadenomas?
Unfortunately, you can’t do anything to lower your risk of fibroadenomas. However, you can take these steps to reduce breast cancer risk:
- Perform regular breast self-exams.
- Visit your primary care provider or gynecologist each year for clinical breast examinations.
- Get regular mammogram screenings (starting at age 40, but earlier if you’re high-risk).
- Don’t drink alcohol. If you do, drink alcohol in moderation only.
- Don’t smoke cigarettes.
- Eat a balanced diet and exercise regularly.
- Maintain a weight that’s healthy for you.
Outlook / Prognosis
What can I expect if I have a fibroadenoma?
Most people who have fibroadenomas or benign breast disease don’t develop breast cancer. Still, you should follow the recommended screening schedule set forth by your provider and report any changes in your breasts.
Can fibroadenomas turn into cancer?
It’s rare for fibroadenomas to turn into cancer. However, you should continue to check the tissue in your breast for new lumps or changes to existing lumps. Becoming aware of how your breasts feel is the best way to recognize changes that could be worrisome.
When should I worry about a fibroadenoma?
Try not to worry about a fibroadenoma. They’re rarely cancerous and most can be left alone. Your healthcare provider is there to answer any questions you have and ease your fears.
Getting a fibroadenoma rarely increases your risk for cancer. However, you should follow your provider’s recommendations on breast cancer screenings just to make sure.
When should I call a healthcare provider about a fibroadenoma?
You should call your healthcare provider if you experience:
- A breast lump that changes or gets bigger.
- Painful lumps.
- A newly discovered breast lump.
- Nipple discharge or rash.
What questions should I ask my provider about a fibroadenoma?
If you have a fibroadenoma, you may want to ask your healthcare provider:
- What’s the best treatment for me?
- How can I tell the difference between a benign and cancerous breast lump?
- How frequently should I get a mammogram or other cancer screening?
- Am I at increased risk for breast cancer?
A note from Cleveland Clinic
Finding a breast lump can be scary, but most lumps aren’t cancerous. Once you know what a benign fibroadenoma feels like, you can quickly notice any suspicious changes and identify new benign lumps. Most people with fibroadenomas don’t need treatment. Some lumps disappear on their own, but never assume a new lump is benign without getting it checked!
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