Fibroadenomas (fy-broe-ad-uh-NO-muhz) are solid, noncancerous breast tumors that occur most often in adolescent girls and women under the age of 30.

You might describe a fibroadenoma as firm, smooth, rubbery or hard with a well-defined shape. Usually painless, a fibroadenoma might feel like a marble in your breast, moving easily under your skin when touched. 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. Treatment may include monitoring to detect changes in the size or feel of the fibroadenoma, a biopsy to evaluate the lump, or surgery to remove it.

Symptoms Causes Complications

Fibroadenomas are solid breast lumps or masses that usually are:

  • Round with distinct borders
  • Easily moved
  • Firm or rubbery
  • Painless

A fibroadenoma may feel like a marble within your breast when you press on it. You can have one or many fibroadenomas. Fibroadenomas range in size from being too small to be felt — detected only by mammogram or ultrasound — to 3 inches (8 centimeters) or more in diameter.

When to see a doctor

In healthy women, normal breast tissue often feels lumpy. If you detect a new breast lump or a change in your breasts — or if a breast lump you've had checked before seems to have grown or otherwise changed — make an appointment with your doctor.

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