- Non-cancerous Breast Conditions
- What is normal breast tissue and what does it do?
- Finding benign breast conditions
- American Cancer Society recommendations for early breast cancer detection
- Diagnosing benign breast changes
- Imaging tests for breast disease
- Nipple discharge exam (nipple smear)
- Types of non-cancerous breast conditions
- Fibrosis and simple cysts
- Lobular carcinoma in situ
- Phyllodes tumors
- Intraductal papillomas
- Granular cell tumors
- Fat necrosis and oil cysts
- Duct ectasia
- Other benign breast conditions
- How benign breast conditions affect breast cancer risk
- For women at increased breast cancer risk
- Additional resources
Fibroadenomas are benign tumors made up of both glandular breast tissue and stromal (connective) tissue. They are most common in young women in their 20s and 30s, but they may be found in women of any age. The use of birth control pills before age 20 is linked to the risk of fibroadenomas.
Some fibroadenomas are too small to be felt and can be seen only under the microscope, but some are several inches across. They tend to be round and have borders that are distinct from the surrounding breast tissue. They often feel like a marble within the breast. You can move them under the skin and they are usually firm and not tender. Some women have only one fibroadenoma, but others may have many.
Fibroadenomas can be diagnosed by fine needle aspiration (FNA) or core needle biopsy. Most fibroadenomas look the same all over when seen under a microscope and are called simple fibroadenomas. But some fibroadenomas contain other components (macrocysts, sclerosing adenosis, calcifications, or apocrine changes). These are called complex fibroadenomas.
Women with fibroadenomas have a slightly increased risk of breast cancer (about 1½ to 2 times the risk of women with no breast changes).
Many doctors recommend removing fibroadenomas, especially if they keep growing or if they change the shape of the breast. Sometimes (especially in middle-aged or elderly women) these tumors stop growing or even shrink on their own, without any treatment. In this case, as long as the doctors are certain the masses are really fibroadenomas and not breast cancer, they may be left in place and watched to be sure they don't grow. This approach is useful for women with many fibroadenomas that are not growing. In such cases, removing them all might mean removing a lot of nearby normal breast tissue, causing scarring that would change the shape and texture of the breast. This could also make future physical exams and mammograms harder to interpret.
It is important for women who have fibroadenomas that have not been removed to have breast exams regularly to make sure they are not growing.
Sometimes one or more new fibroadenomas grow after one is removed. This means that another fibroadenoma has formed—it does not mean that the old one has come back.
Last Medical Review: 08/24/2012
Last Revised: 08/24/2012