Breast Fibroadenomas

What Are Fibroadenomas?

Fibroadenomas are solid tumors consist of fibrous and glandular tissue that form a mass. They can occur in one or both breasts. Fibroadenomas vary in size, with an average size of about 1 inch, and tend to grow slowly. While typically painless, larger fibroadenomas can become slightly sore or tender before a woman’s menstrual period. They can also grow larger during pregnancy.

Fibroadenomas can usually be identified by characteristics such as:

• Round or oval lump with smooth, defined borders
• Firm or rubbery texture
• Moves easily when touched

Some fibroadenomas may shrink over time and can disappear on their own without treatment. They also tend to shrink after menopause.

What Causes Fibroadenomas?

Experts are unclear on what causes fibroadenomas but believe that the hormone estrogen play a role. Fibroadenomas tend to grow larger during pregnancy, when estrogen levels are higher, and shrink when estrogen levels fall during menopause. Genetics may also be a factor.

Fibroadenomas most often occur in younger women who have a period, although they can also develop in menopausal women who are on hormone therapy. Black women also have a slightly higher risk of developing a fibroadenoma.

Fibroadenomas are harmless in the vast majority of cases. However, they can very rarely contain cancerous tissue so they should always be monitored by a healthcare provider.

Diagnosing and Treating Fibroadenomas

Fibroadenomas can often be diagnosed by a healthcare provider by a simple physical exam. However, your provider will likely conduct additional testing to rule out more serious conditions such as cancer. These include:

• Mammogram: This imaging test uses low-dose X-ray technology to capture pictures of breast tissue.
• Breast ultrasound: An imaging test that uses sound waves to create pictures of the inside of the breast.
• Fine needle aspiration: This biopsy procedure uses a needle to collect a sample from the tumor to examine in a lab.

Since fibroadenomas are largely harmless, most do not require treatment. In these cases, your provider will continue to monitor the fibroadenoma for changes in size or shape. As long as the tumor is benign and is not causing discomfort or pain, it is safe to leave it in place. However, If a fibroadenoma continues to grow larger, becomes painful or changes the shape of the breast, your provider may recommend surgical removal.

While most fibroadenomas do not lead to cancer, there is one type that can be linked to an increased risk for cancer in people with a family history of breast cancer. That’s why regular monitoring of the fibroadenoma, along with yearly screening mammograms for women over 40, is so important.