Fibroadenomas

Definition

Fibroadenomas (fi-bro-ad-uh-NO-muhz) are solid, noncancerous tumors that often occur in women during their reproductive years. A fibroadenoma is a firm, smooth, rubbery or hard lump with a well-defined shape. It moves easily under your skin when touched and is usually painless. Fibroadenomas are more common among women in their 20s and 30s.

Fibroadenomas are one of the most common breast lumps in premenopausal women. Fibroadenomas range in size from less than 1 centimeter to several centimeters in diameter. They can get bigger during pregnancy and breast-feeding.

Treatment may include careful monitoring to detect changes in the size or feel of the fibroadenoma or surgery to remove it.

Symptoms

Fibroadenomas are solid breast lumps or masses that usually are:

• Round with distinct borders
• Easily moved
• Firm or rubbery
• Painless

A fibroadenoma may feel like a marble within your breast when you press on it. You can have one or many fibroadenomas. They usually grow to about 1 to 2 centimeters (cm) in size, but they can become even larger. A fibroadenoma that measures 5 cm or greater is referred to as a giant fibroadenoma.

When to see a doctor
Normal breast tissue in healthy women often feels lumpy or nodular. If you detect the presence of any new breast lumps, however, or if a previously evaluated breast lump seems to have grown or otherwise changed, make an appointment with your doctor to get it checked out

Causes

Each of your breasts contains 15 to 20 lobes of glandular tissue, arranged like the petals of a daisy. The lobes are further divided into smaller lobules that produce milk during pregnancy and breast-feeding. Small ducts conduct the milk to a reservoir that lies just beneath your nipple. Supporting this network is a deeper layer of connective tissue called stroma. Fibroadenomas are made up of both glandular (lobular) tissue and connective (stromal) tissue.

The cause of fibroadenomas is unknown. However, fibroadenoma development is probably related to reproductive hormones. Fibroadenomas occur in greater frequency during your reproductive years, can increase in size during pregnancy or with estrogen therapy, and tend to shrink after menopause.

Complications

Breast cancer risk increases with some types of fibroadenomas.

Simple fibroadenomas

Most fibroadenomas are simple fibroadenomas. These masses have distinct borders and uniform-looking cells. Simple fibroadenomas do not increase your risk of breast cancer, especially if you have no family history of breast cancer.

Complex fibroadenomas

These fibroadenomas contain cysts, enlarged breast lobules (adenosis) or bits of dense, opaque tissue called calcifications. Complex fibroadenomas don't turn into breast cancer, but they do increase your risk of later developing breast cancer by a factor of about 2 to 3. However, your overall risk of developing breast cancer after being diagnosed with a complex fibroadenoma remains low.

Tests and diagnosis

Evaluation of a fibroadenoma usually begins after you or your doctor has identified a breast lump. The process may involve the following tests or exams:

•  Clinical breast exam.Your doctor physically examines the breast lump and checks for any other problem areas in your breasts. Be prepared to answer questions such as when you first noticed the lump, whether it seems to have gotten bigger, if you have any nipple discharge and if you notice any changes in the size of the lump during your menstrual cycle.
• Mammography. Mammography uses a series of X-rays to produce an image (mammogram) of suspicious areas in your breast tissue. A fibroadenoma usually appears on a mammogram as a breast mass with smooth, round edges, distinct from surrounding breast tissue. To evaluate a suspected fibroadenoma, mammograms are routinely performed for women age 30 and older.
• Breast ultrasound. If you're younger than age 30, your doctor may opt for a breast ultrasound instead of a mammogram to evaluate a breast lump. Dense breast tissue in younger women makes mammograms difficult to interpret. Breast ultrasound might also be performed as a follow-up to a mammogram regardless of your age. Breast ultrasound can help your doctor determine whether a breast lump is solid or fluid-filled. A solid mass is more likely a fibroadenoma, and a fluid-filled mass is a cyst. Some doctors, however, opt to skip ultrasound and perform fine-needle aspiration instead.
• Fine-needle aspiration. Through a thin needle inserted into the breast lump, your doctor attempts to withdraw the contents of the breast lump. If no fluid comes out, the lump is solid and most likely a fibroadenoma. A sample of cells may be collected and sent for analysis to check for the presence of cancer (fine-needle aspiration biopsy).
•  Core needle biopsy. To be certain that a solid breast lump is a fibroadenoma and not breast cancer, your doctor will probably recommend a biopsy. Core needle biopsy uses a large needle to obtain several tissue samples from the breast lump to send for analysis.

Treatments and drugs

Surgery to remove a fibroadenoma

A fibroadenoma, once it's identified, can continue to grow and may change the shape of your breast. Your doctor might recommend surgery to remove the fibroadenoma if one of your tests — the clinical breast exam, an imaging test or a biopsy — is abnormal. You may also consider surgical removal if leaving the fibroadenoma in place makes you anxious.

The procedure to remove a fibroadenoma is called a lumpectomy or excisional biopsy. The surgery may be performed using local or general anesthesia. A surgeon makes an incision in your breast and removes the breast lump plus some surrounding breast tissue. The tissue sample is then sent to a lab for analysis to confirm that the breast lump is a fibroadenoma and not breast cancer.

After a fibroadenoma is removed, it's possible that one or more new fibroadenomas may develop. You may need another surgery to remove new fibroadenomas.

When surgery isn't needed

If your doctor is reasonably certain that your breast lump is a fibroadenoma and not breast cancer — based on the results of the clinical breast exam, imaging test or biopsy — surgery may be unnecessary.

For younger women — those who most commonly develop fibroadenomas — surgery to remove the breast mass might distort the shape and texture of the breast and leave scar tissue that complicates future breast exams. In older women — usually past their 30s — fibroadenomas may stop growing or even shrink on their own.

If you choose not to have a fibroadenoma removed, continued monitoring is important to make sure it doesn't grow larger. At any time that you become overly anxious about the fibroadenoma, you can reconsider surgery.