Fibroadenomas are solid, benign breast lumps composed of glandular tissue that most commonly occur in women under the age of 30 and are the most common breast lumps found in women. They may however occur in women over this age due to the fact that most benign breast disorders arise on the basis of normal changes occuring in the breast throughout the various stages of reproductive life (menopause included). These lumps may range in size from smaller than a marble to as large as a golf ball and may appear suddenly and stay the same size, shrink or continue to grow. These lumps are influenced by hormones and often change size over the menstrual cycle or in pregnancy.
Fibroadenomas are usually rubbery, firm and well defined shape, but they can be difficult to feel properly. If you push on the lump it may feel like a marble and you will probably find that it moves away from beneath your fingers. This is why some people call a fibroadenoma a ‘breast mouse’. They are often painless however they can be sensitive to touch and most women find that the discomfort is increased in the few days prior to their menstrual period (increased estrogen levels).
Most fibroadenomas are left alone and not treated and may resolve on their own. While fibroadenomas are not cancerous, it is sometimes difficult for clinicians and women to feel completely confident that a lump is not cancerous. Some of these lumps need to be removed or have a biopsy to stop this concern. For most women, having an unusual breast change is upsetting. It can bring up many different feelings and worries. It’s understandable to fear cancer. It’s also common to find tests stressful and invasive.