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Breast cancer

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Fibroadenomas are solid, benign tumours of the breast tissues. They are common in young women between the ages of 20 and 30. Women may have one or several fibroadenomas, and they can occur in one or both breasts.

There are 2 types of fibroadenomas:

  • simple fibroadenoma – most common type of fibroadenoma
  • complex fibroadenoma – contain a mixture of cysts (fluid-filled sacs), enlarged breast lobules and calcifications

Simple fibroadenomas do not increase a woman’s risk of developing breast cancer. Complex fibroadenomas do not become malignant (cancerous), but they may slightly increase a woman’s risk of developing breast cancer in the future.

Risk factors

There are no known risk factors for fibroadenomas. It is thought that they are caused by the hormoneshormonesA substance that regulates specific body functions, such as metabolism, growth and reproduction. that control a woman’s menstrual cycle. Fibroadenomas are more common in women of reproductive age and often disappear after menopausemenopauseThe time in a woman’s life when her ovaries stop producing estrogen and she has not had a menstrual period for 12 months. Most women start menopause between 45 and 55 years of age..

Signs and symptoms

The signs and symptoms of fibroadenomas may include a lump that feels:

  • round
  • rubbery and smooth
  • well-defined with clear borders or edges
  • easy to move
  • painless

A woman can have one or many fibroadenomas in her breast. Most fibroadenomas are 1–2 cm in size, but can grow as large as 5 cm (giant fibroadenoma).


If the signs and symptoms of a fibroadenoma are present, or if the doctor suspects a fibroadenoma, tests will be done to make a diagnosis. Tests may include:


Treatment options for fibroadenoma may include:

  • watching the fibroadenoma over time
  • surgery to remove the fibroadenoma


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