Fibroadenomas are the commonest cause of lumps in young women and are also known as ‘breast mice’. Young women’s breasts are usually quite dense and fibroadenomas can be found as part of normal breast architecture. The breast undergoes normal changes, becoming less dense as women get older. Hence fibroadenomas become less common with age. Having a fibroadenoma does not increase the risk of getting breast cancer.
How do they present?
Fibroadenomas normally present as palpable lumps, although both ultrasound scans and mammograms can discover those that are very small. To a breast specialist, these lumps have a characteristic feel to them. Normally they are mobile and soft, with regular edges.
If you feel a lump, you should seek medical review and ask to be referred to a specialist where you will have a triple assessment performed in a breast clinic. If you are below the age of 40 years, you will most likely only have an ultrasound scan. This is because the dense nature of young women’s breasts means that a mammogram is not a useful tool to detect breast changes in this age group.
This is what a fibroadenoma looks like when scanned with an ultrasound scan
A fibroadenoma has characteristic features, not only to feel, but also on an ultrasound scan as seen in this image above.
However, if you are above a certain age, normally 25 years, then a biopsy (needle test) may also be performed to be certain of the diagnosis.
Can a fibroadenoma develop to become cancer?
Fibroadenomas are benign lumps (non-cancerous) that don’t turn into cancers and therefore can be safely left alone. We know that fibroadenomas can fluctuate in size and we think that hormonal influences affect this. Fibroadenomas can remain static in size, but sometimes can get smaller and disappear. A fibroadenoma can also get bigger and in this instance, you may be advised to consider having a small operation to remove it. This is true especially if it increases in size significantly over a short period of time. In this scenario, we would normally like to exclude a condition called a phyllodes tumour. Surgery may also be offered if the fibroadenoma is large or if it demonstrates a complex cellular architecture.
Do I need to be followed up?
A diagnosis of a fibroadenoma does not require further follow up and you do not need regular scans. There is no increase in the risk of breast cancer.
The most important thing is to remain breast aware. If the fibroadenoma lump gets bigger or changes in character in any way then you should seek medical advice. Otherwise, no further treatment is necessary.