Fibroadenoma

What is fibroadenoma?

A fibroadenoma is a benign (non-cancerous) breast tumor. It is the most common kind of breast tumor in young women. Fibroadenomas result from overgrown cells forming a mass (-oma) of breast tissue including fibrous (fibro-) and glandular (-adeno-) components.

Some fibroadenomas remain unnoticed until a breast exam or mammogram; however, they may be felt as a mobile, rubbery mass in your breast tissue that can cause some discomfort or tenderness.

Once a diagnosis of a fibroadenoma is likely, further testing or procedures are usually not necessary. Fibroadenomas can simply be monitored and otherwise left alone, as long as they are not significantly impacting your quality of life.

You should visit your primary care physician to confirm the diagnosis and discuss treatment options.

Fibroadenoma symptoms

Since this a benign condition, a fibroadenoma should only cause local symptoms in the area of the tumor itself, if any. The definitive diagnosis requires appropriate workup by a medical professional. For young women, this will often begin with a breast ultrasound, since mammograms are less effective in younger women. Further workup may involve one or more techniques including mammogram, MRI, fine-needle aspiration or biopsy.

Benign symptoms

The presence of these symptoms may help you and your physician determine that you have a fibroadenoma and not a more concerning mass. However, not every fibroadenoma is mobile and not every cancerous tumor is irregular or lumpy, as described below. Benign symptoms include:

• Rubbery mass in breast tissue: When noticeable, a fibroadenoma will be felt as a rubbery mass within the breast tissue. They are slow-growing but can reach a substantial size before being noticed.
• Mobility: Fibroadenomas are usually mobile and not fixed to the chest wall, which means they are able to be moved around within the surrounding tissue. This mobility is an important diagnostic clue as it is classically associated with benign tumors such as fibroadenomas. In contrast, malignant breast cancers are more likely to invade the chest wall and become fixed in place. Breast cancer is also more likely to have an irregular, lumpy body compared to the smoother, well-defined border of a typical fibroadenoma.
• Discomfort: Though they do not cause systemic symptoms or impair function, a fibroadenoma can cause local discomfort. It is less common for a fibroadenoma itself to be painful, though tenderness does sometimes occur around the time of menstruation. They can also press on neighboring tissues, and larger fibroadenomas, in particular, can cause bras or tighter clothing to fit abnormally.

More serious symptoms

"Red flag" symptoms not commonly associated with fibroadenomas may be coincidental but are also common features of several kinds of breast cancer. Anyone with a breast mass and any of these "red flag" symptoms should seek care sooner rather than later. These symptoms include:

• Weight loss
• A rash near the mass
• Abnormal nipple discharge
• Additional lumps and bumps: These may be in nearby areas such as the underarm or neck.

Fibroadenoma causes

As with most benign growths, the specific cause of a fibroadenoma is typically not known. They are most commonly found in women 15 to 35 years old.

Estrogen levels

Many fibroadenomas are at least partially sensitive to the influence of sex hormones, particularly estrogen. Estrogen levels are higher in women of reproductive age than in prepubescent girls or postmenopausal women, possibly explaining the higher prevalence of fibroadenoma in that age range. Since sex hormones control the proliferation of normal breast tissue, it makes sense that fluctuations in sex hormone levels can similarly stimulate abnormal proliferation of breast tissue cells in a fibroadenoma.

Other hormonal imbalances

Like most breast tumors, fibroadenomas occur almost exclusively in women. When seen in men, they are often attributed to substantial hormone imbalance. Such imbalance can be caused by an underlying endocrine disorder or by anti-androgen therapies used to treat male genitourinary cancers. Such cases are very rare.

Treatment options and prevention for fibroadenoma

It is important to reiterate that a fibroadenoma is entirely benign and not a form of breast cancer, and is almost never dangerous. Details regarding the diagnosis, reasons for removal, as well as how fibroadenoma are removed are described below.

Further diagnosis details

Surgical removal of a concerning mass is rarely necessary to definitively rule out the presence of cancer. Far more often, particularly for women under 30 years old, the diagnosis can be sufficiently reliable on clinical history and physical exam alone. Many women and their medical providers do not pursue further workup if a benign mass is presumed, though this decision should be made on a case-by-case basis between you and your physician.

Removal for further examination

Again, this reason for removal is rare. In some cases, a likely fibroadenoma should be surgically removed so it can be examined under a microscope. This allows pathologists to verify the diagnosis of fibroadenoma. More importantly, it allows them to rule out other breast lesions which can look similar to specific subtypes of fibroadenoma. For example, the so-called "giant" fibroadenomas (measuring over 10 centimeters) can be particularly hard to distinguish from a slightly higher-risk mass known as a phyllodes tumor. Removal of these largest fibroadenomas allows both a verification of the diagnosis and alleviation of the discomfort a mass that size can cause.

Removal for cosmetic reasons

Removals can also occur for cosmetic reasons, rather than diagnostic reasons. It is understandable that some women have anxiety over even a benign mass, and you may prefer to have it removed just for peace of mind. It is important to be open with your physicians about your values and concerns regarding a breast mass, or any medical condition for that matter. This will help them to understand your perspective and better work with you to make personalized medical decisions, for example, balancing the risks and benefits of potential surgery.

How fibroadenomas are removed

Fibroadenomas may be removed by an excisional breast biopsy — a short, outpatient procedure under general anesthesia. They may also be destroyed by cryoablation or radiofrequency ablation.

Prevention

The following methods of prevention may be helpful, but not guaranteed.

• Having lower or regulated estrogen levels: While there is no way to entirely prevent fibroadenoma formation, a decreased risk is associated with reduced lifetime estrogen exposure — hormonal contraception (oral birth control), late puberty, or early menopause.
• Maintaining a healthy lifestyle: A healthy lifestyle has also been associated with a lower risk of developing a fibroadenoma, including not smoking, regular exercise, and maintaining a healthy body weight. Some studies have even found an association between lower fibroadenoma risk and the consumption of a diet rich in fruits and vegetables.

Prognosis

Often, a fibroadenoma will regress and disappear on its own without any intervention. This is especially true for hormone-sensitive fibroadenomas, which are particularly likely to regress after menopause. With monitoring, fibroadenomas can otherwise be left alone as long as they do not cause you significant discomfort.

When to seek further consultation for fibroadenoma

You should go see a physician sooner than later if you experience any "red flag" symptoms, such as a rash, nipple discharge, or weight loss.

If you have been diagnosed with a fibroadenoma or mass

You should see a physician and schedule routine follow-ups for breast exams to make sure there are no new or changing breast masses. In the case of fibroadenomas, an invasive workup is often unnecessary, as discussed prior. Clinical examination by a gynecologist or primary care practitioner can be sufficient to identify those lumps and bumps that are extremely unlikely to be dangerous.

Maintaining current and future breast health

There is a slightly increased risk (1.5 times) of breast cancer in some women who have had a simple fibroadenoma. The risk can be slightly increased in women with a rarer "complex" form of fibroadenoma, whose appearance on a biopsy shares microscopic features with some precancerous lesions.

Since there is no increased cancer risk from most fibroadenomas, most women have no need for additional imaging or earlier mammograms. The American College of Obstetricians and Gynecologists currently recommends screening mammography be offered to all women starting at age 40, beginning no later than age 50. Earlier screening is needed for women with a strong family history of breast cancer or several other specific cancers.