Fibroadenomas are solid, noncancerous breast tumors that occur most often in adolescent girls and women under the age of 30. Fibroadenomas vary in size, and they can get bigger or even shrink on their own. Fibroadenomas are among the most common breast lumps in young women. The exact cause of fibroadenomas is not known.
Hormones such as estrogen may play a part in the growth and development of the tumors. Taking oral contraceptives before the age of 20 has been associated with a higher risk of developing fibroadenomas. These tumors may grow, particularly during pregnancy. During menopause, they often shrink. It is also possible for fibroadenomas to resolve on their own.
Fibroadenomas are usually single lumps. About 10% to 15% of women have several lumps that may affect both breasts. Lumps may be any of the following:
Procedures to remove a fibroadenoma include:
Fibroadenomas are the most common breast tumor in adolescent women. They can also occur in a small number of post-menopausal women. Their incidence declines with increasing age, and, in general, they appear before the age of thirty years.