Fibroadenoma of the breast

Fibroadenoma is a term that medics use to describe a broad range of solid, benign breast lesions that commonly affect premenopausal women.

Fibroadenomas often present as a palpable breast lump that might feel firm, smooth, rubbery or hard, perhaps like a pea or a grape. These breast lesions tend to be painless but will often move easily under the skin.

Fibroadenomas usually develop in the normal breast from the lobules, which are the glands responsible for milk production. The surrounding tissue and breast ducts grow over the lobule creating a benign breast tumor or lump.

Fibroadenomas are most common in women in their 20’s and carry very little risk of progressing to breast cancer. If you find any unusual hard lump in your breast it is important to have a clinical examination with your physician or breast care center as soon as possible.

What does the word benign actually mean?

Benign is what you will be after you be eight.

Benign, in this case, means it is not cancer or malignant.

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Composed of fibrous and glandular tissue

A fibroadenoma consists of fibrous and glandular connective tissue that has grown more rapidly than usual. Also, the growth pattern may be unusual, resulting in a breast lump. A fibroadenoma can range in size from under 1 cm all the way up to several centimetres in diameter. A fibroadenoma can occur singularly, in groups or as a complex.

Hormones affect fibroadenomas and so the lump (or lumps) tends to fluctuate (or increase) in size during the menstrual cycle, pregnancy and breastfeeding. Hormone replacement therapy and oral contraception can also affect the size of a fibroadenoma.

Every woman will worry that any breast lump may be or lead to breast cancer.

Yes, but carry on reading and we hope that you will be reassured.

Worrying is a bit like walking around with an umbrella waiting for it to rain.

Fibroadenoma alone does NOT increase the risk of breast cancer

Fibroadenomas themselves do NOT pose any risk of breast cancer development throughout the breast tissue.

However, on many older websites, including ours, specialists suggest that a fibroadenoma may be associated with an increase in the likelihood of developing breast cancer.

Some specialists still hold to this theory, so let’s take a look at where this comes from and latest developments.

It may be that in the years before ultrasound-guided core biopsy, doctors and breast surgeons would “guess” that a breast lump was a fibroadenoma. Obviously, a small percentage of those guesses would be wrong.

The patient may later have a breast biopsy that shows a lobular carcinoma, ductal carcinoma, phyllodes tumor, or a cystosarcoma phyllodes. But nowadays, those with benign-looking nodules will tend to have a core-biopsy (or even an excisional biopsy) anyway, for diagnostic purposes. If a biopsy proves that a breast lump IS a fibroadenoma this result is benign with no increase in the risk for breast cancer.

So, to clarify, I think that the statistics can get confusing. In my experience, women with a fibroadenoma do NOT have a higher breast cancer risk per-se. However, many of these women with fibroadenomas, also have denser breast tissue, and this does carry a higher risk for breast cancer.

So it is thought that Fibroadenomas are related to hormones.

Hormones? I’m fine. I hate you. I love you. Is that ice cream? Come here. Get away. Donuts.

Causes of fibroadenoma

The cause of a fibroadenoma is unknown, but there is a link with abundant estrogen, as they are common in young women. Medics believe that fibroadenoma formation may be related to the hormone-receptor mechanisms.

Dear whoever is reading this, I hope that you have a reason to smile today.

Treatments for breast fibroadenoma

Usually, a biopsy will be taken with a fine needle aspiration(FNA) or core biopsy to confirm the benign diagnosis by examining the appearance and cytology of the epithelial cells. Nowadays a core biopsy is much more common than a fine needle aspiration.

Most fibroadenomas are simply left alone. However, some women prefer to have surgical removal of the lump as they do have a tendency to grow during pregnancy or hormonal fluctuations. An alternative to surgery is laser ablation whereby a laser beam is directed to the fibroadenoma and destroys it. This method has the advantage of leaving minimal scarring.

On a different note, every woman should give themselves a breast self-examination or attend screening regularly. Furthermore, surgeons perform most biopsies and procedures under local anesthetic so they should not be painful at all.

Here are a few Q&A’s…

Where do fibroadenomas occur?

In the breast. Here’s a fun fact: When someone has multiple nodules, it is probably an indication that they are benign fibroadenomas. If a woman has a single fibroadenoma then it is likely that multiple fibroadenomas may develop.

What are the fibroadenoma symptoms?

Round with distinct borders, easily movable under the skin, firm or rubbery, and painless.

What causes fibroadenoma?

This is unknown. However, reproductive hormones may play a role in the development of a fibroadenoma.

When does the fibroadenoma grow the most?

A fibroadenoma can become larger during pregnancy or when breastfeeding or with the use of hormone therapy. Interestingly, fibroadenomas may even shrink after menopause when hormone levels decrease.

Are there any fibroadenoma complications?

It does not affect your risk of breast cancer. However, your breast cancer risk might increase a little bit if you have a complex fibroadenoma. This type may contain abnormal cysts or dense, opaque tissue called calcifications.

What are the tests/diagnosis?

Mammography, breast ultrasound, fine-needle aspiration, and core needle biopsy. This all depends on your age and the characteristics of the lump.

I have been told that I have fibrocystic breast disease is this the same as a fibroadenoma?

Fibrocystic disease is an umbrella term that covers a whole range of benign breast diseases. These conditions include:-

Radial scar
Breast cysts
Adenosis
Fibroadenoma
Hyperplasias such as ductal hyperplasia and lobular hyperplasia (although atypical lobular hyperplasia is more concerning).

I have had a fibroadenoma removed but it appears to have come back, is this likely?

Yes, local recurrence is possible. If you have had one or more fibroadenomas in the past then you are more likely to have them again. Furthermore, for unknown reasons, certain ethnic groups, such as African-American women are more likely to develop fibroadenomas.

Why is surgery sometimes avoided?

Surgery can distort the shape and texture of the breast. Also, fibroadenomas sometimes shrink or disappear on their own. In addition, the breast may have multiple fibroadenomas that appear to be stable (no changes in size on ultrasound in comparison to earlier ultrasounds).

References

Dupont W, Page D, Parl F, Vnencak-Jones C, Plummer W, Rados, M. (1994) Long-Term Risk of Breast Cancer in Women with Fibroadenoma. The New England Journal of Medicine, July 1994Vol. 331,1 p. 10-15. https://www.ncbi.nlm.nih.gov/pubmed/8202095
Carter CL, Corle DK, Micozzi MS, Schatzkin A, Taylor PR. (1988) A prospective study of the development of breast cancer in 16,692 women with a benign tumor in the breast. Am J Epidemiol 1988;128:467-477. https://www.ncbi.nlm.nih.gov/pubmed/3414655
Courtillot C. (et al). Benign breast diseases. J Mammary Gland Biol Neoplasia. 2005; 10:325-335. https://www.ncbi.nlm.nih.gov/pubmed/16900392
Gordon PB, Gagnon FA, Lanzkowsky L. (2003) Solid breast masses diagnosed as fibroadenoma at fine-needle aspiration biopsy: acceptable rates of growth at long-term follow-up. Radiology. 2003 Oct;229(1):233-8. https://www.ncbi.nlm.nih.gov/pubmed/14519878
Levi F, Randimbison L, Te VC, La Vecchia C. (1994) Incidence of breast cancer in women with fibroadenoma. Int J Cancer 1994 Jun 1;57(5):681-3 https://www.ncbi.nlm.nih.gov/pubmed/8194875
Carter BA, Page DL, Schuyler P, Parl FF, Simpson JF, Jensen RA, Dupont WD. (2001) No elevation in long-term breast carcinoma risk for women with fibroadenomas that contain atypical hyperplasia. Cancer 2001 Jul 1;92(1):30-6 https://www.ncbi.nlm.nih.gov/pubmed/11443606
Sapino A, Bosco M, Cassoni P, Castellano I, Arisio R, Cserni G, Tos AP, Fortunati N, Catalano MG, Bussolati G. (2006) Estrogen receptor-beta is expressed in stromal cells of fibroadenoma and malignant phyllodes tumors of the breast. Mod Pathol. 2006 Apr;19(4):599-606. https://www.ncbi.nlm.nih.gov/pubmed/16554735