BENIGN BREAST DISEASES

FIBROADENOMA

What is a Fibroadenoma?

A Fibroadenoma is a non cancerous (benign) breast lump. It is made up of fibrous tissue (connective tissue) and glandular tissue. ”Oma” means tumour or lump, “fibro” means fibrous and “adeno” means glands. They are often mobile, hence called a “breast mouse”.

What is the incidence of Fibroadenoma?

Fibroadenoma account for approximately 13% of all symptomatic breast lumps.

When does it occur?

Although it can develop at any age it usually occurs in the late teens and early twenties when the breast lobular development is the greatest. 

What causes Fibroadenoma?

The cause of Fibroadenoma is unknown. Hormonal factors are thought to play a part as Fibroadenoma is known to fluctuate during the menstrual cycle and during pregnancy. Fibroadenoma may present in women on hormone replacement therapy and tend to get smaller after the menopause.

What is the natural history of Fibroadenoma?

In most women, only one Fibroadenoma is found. Occasionally, there is more than one and sometimes they occur in both breasts. Fibroadenoma varies in size.  In women less than 40 years of age majority of Fibroadenoma does not change size (80%), some get smaller or completely disappear (15%) and some increase in size (5-10%).

What is a juvenile Fibroadenoma or a giant Fibroadenoma?

Although rare some Fibroadenoma grow rapidly within a short time and cause marked asymmetry of the breast.  Tumours greater than 5 cms are termed as giant Fibroadenoma and are common in the African countries.  Juvenile fibro adenomas are characteristically seen in teenagers or in the early twenties.

Is there any association between Fibroadenoma and breast cancer?
Fibroadenoma is not a precancerous condition. It does not increase the risk of cancer in the rest of the breast tissue. Rare occurrences of cancer within a Fibroadenoma have been reported in the literature. Multiple Fibroadenoma are associated with a slightly increased risk of developing breast cancer. 

How do they present?

In young women they may present as a lump. Fibroadenoma is usually painless, but in some may feel tender or even painful. It may also be seen as an incidental finding during breast imaging (ultrasound /mammogram (X ray of the breast) or MRI scan) for other problems in the breast. 

Which patients with breast lumps should be referred to the hospital?

URGENT REFERRALS

Women aged 30 years and older

With a discrete lump that persists after their next period, or presents after menopause

Women aged younger than 30 years

With a lump that enlarges

With a lump that is fixed and hard  

And who have other reasons for concern such as family history

NON URGENT REFERRALS

Women aged younger than 30 years with a lump.   

How is a Fibroadenoma diagnosed?

If you are below 25 years of age you will have a physical examination of the breast and an ultrasound examination. You may not usually undergo a needle test or a biopsy unless the ultrasound image is atypical or you have risk factors such as a family history of breast cancer. The reason being it is extremely rare to have breast cancer in this age group and ultrasound confirmation is enough evidence.

If you are over 25 years of age you will have a physical examination of the breast and an ultrasound examination.  Ultrasound is preferred in younger women with dense breasts as X rays of the breast (mammograms) are difficult to interpret and Fibroadenoma may not be visible. However in less dense breasts (fatty breasts) mammogram may also be done.  In majority of patients over 25 years of age, ultrasound or X ray of the breast alone may not be enough to confirm the diagnosis of Fibroadenoma.  The specialist may attempt to sample cells from the lump by doing a needle test (fine needle aspiration). Cells are studied by the pathologist to confirm a diagnosis of Fibroadenoma.  Because of the high proportion of fibrous tissue relative to epithelial tissue in Fibroadenoma, needle test (fine needle aspiration) may be insufficient for diagnosis. Hence most specialists will recommend a core biopsy to obtain a sample of tissue rather than cells to confirm the diagnosis of Fibroadenoma. The sample is processed by the pathologist and may take up to 48 hours for the results. 

How is Fibroadenoma managed?

The management again depends on your age, your preference and the results of the tests.   

Age less than 25

Once confirmed that a lump is a Fibroadenoma, you will be reassured and discharged. There is no need to remove it. It can be safely left alone unless you wish that the lump is removed. After discharge by the specialist you should get in touch with your doctor if the lump increases in size. 

Age more than 25

If a diagnosis of Fibroadenoma is confirmed with core biopsy you will be reassured and discharged. It can be safely left alone unless you wish that the lump is removed.  After discharge by the specialist you should get in touch with your doctor if the lump increases in size. 

In all patient 

Excision of the lump is recommended if

The lump significantly increases in size,

Or where the lump is larger than 4 cms in size

Or if the presence of the tumour causes asymmetry in the breast

Or if there is a concern about increased activity in the lump

Surgical excision

The operation is simple and usually done as a day case. It can be done under a local anaesthetic or under a general anaesthetic and you can go home the same day.  Removing a Fibroadenoma doesn’t usually affect the shape of the breast, as normal breast tissue will fill the space where it

used to be.

Mammotome excision

Lumps can also be removed using a vacuum assisted needle under the guidance of ultrasound without having surgery.  It will be done as a day case with local anaesthetic and you can go home the same day.  The lump is sucked up through a needle until it is seen to disappear. 

 The lump removed either surgically or with a mammotome is routinely sent to the laboratory for examination under the microscope.  The results of this test are usually available the following week. 

Fibroadenoma can occasionally grow back but it is rare.  It is possible to develop another one in either breast in the future.

Will surgical removal of the lump affect the ability to breast feed?

Removing a Fibroadenoma causes no harm to the breast and won't affect the ability to breastfeed.

For more information contact: sasi@mybreastcare.org

This information sheet is aimed at women who have been examined by a breast specialist and found to have a benign Fibroadenoma (non cancerous) condition. It is not a substitute for the advice of a qualified doctor. It is intended to provide information for better understanding and reassurance