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Fibroadenomas are small, solid, rubbery noncancerous lumps composed of fibrous and glandular tissue.

Fibroadenomas usually appear in young women, including teenagers. The cause is unknown.

The lumps are easy to move and have clearly defined edges that can be felt during self-examination. They may feel like small, slippery marbles. These characteristics indicate to a doctor that the lumps are less likely to be cancerous. Nonetheless, to be sure that they are not cancerous, the doctor usually removes the lumps. A local anesthetic is used.

Fibroadenomas often recur. If several lumps have been removed and found to be noncancerous, a woman and her doctor may decide against removing new lumps that develop.

Last full review/revision November 2008 by Victor G. Vogel, MD, MHS