Fibroadenoma is a common benign (non-cancerous) breast tumor that is made up of glandular and connective tissue. It usually develops in young women, typically between the ages of 15 and 35, but can occur at any age.

Fibroadenomas are usually painless and are often discovered during routine breast examinations or imaging studies, such as mammography or ultrasound. They may feel like a smooth, rubbery lump, and can be mobile within the breast tissue. Fibroadenomas vary in size and can grow over time, but they are not considered to be serious medical conditions.

In most cases, no treatment is required for fibroadenomas, but your healthcare provider may recommend monitoring the lump through regular breast exams and imaging studies to ensure that it remains stable in size and texture. If the fibroadenoma causes pain or is growing rapidly, it may be surgically removed. In addition, a biopsy may be performed to confirm the diagnosis and rule out the possibility of cancer.

While fibroadenomas are not cancerous, it's important to be aware of any changes in your breast tissue and report any concerns to your healthcare provider. If you notice any new lumps or changes in the texture or appearance of your breast tissue, it's important to have them evaluated promptly.

The cause of fibroadenomas is unknown, but they might be related to reproductive hormones. Fibroadenomas occur more often during your reproductive years, can become bigger during pregnancy or with use of hormone therapy, and might shrink after menopause, when hormone levels decrease.

Types of fibroadenomas

In addition to simple fibroadenomas, there are:

• Complex fibroadenomas. These can contain changes, such as an overgrowth of cells (hyperplasia) that can grow rapidly. A pathologist makes the diagnosis of a complex fibroadenoma after reviewing the tissue from a biopsy.
• Juvenile fibroadenomas. This is the most common type of breast lump found in girls and adolescents between the ages of 10 and 18. These fibroadenomas can grow large, but most shrink over time, and some disappear.
• Giant fibroadenomas. These can grow to larger than 2 inches (5 centimeters). They might need to be removed because they can press on or replace other breast tissue.
• Phyllodes tumor. Although usually benign, some phyllodes tumors can become cancerous (malignant). Doctors usually recommend that these be removed.

In many cases, fibroadenomas require no treatment. However, some women choose surgical removal for their peace of mind.

Nonsurgical management

If your doctor is reasonably certain that your breast lump is a fibroadenoma — based on the results of the clinical breast exam, imaging test and biopsy — you might not need surgery.

You might decide against surgery because:

• Surgery can distort the shape and texture of the breast
• Fibroadenomas sometimes shrink or disappear on their own
• The breast has multiple fibroadenomas that appear to be stable — no changes in size on an ultrasound compared to an earlier ultrasound

If you choose not to have surgery, it's important to monitor the fibroadenoma with follow-up visits to your doctor for breast ultrasounds to detect changes in the appearance or size of the lump. If you later become worried about the fibroadenoma, you can reconsider surgery to remove it.

Surgery

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 or if the fibroadenoma is extremely large, gets bigger or causes symptoms.

Procedures to remove a fibroadenoma include:

• Lumpectomy or excisional biopsy. In this procedure, a surgeon removes breast tissue and sends it to a lab to check for cancer.
• Cryoablation. Your doctor inserts a thin, wand-like device (cryoprobe) through your skin to the fibroadenoma. A gas is used to freeze and destroy the tissue.

After a fibroadenoma is removed, it's possible for one or more new fibroadenomas to develop. New breast lumps need to be assessed with a mammogram, ultrasound and possibly biopsy — to determine if the lump is a fibroadenoma or might become cancerous.