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Breast Density

What is breast density?
Breasts come in all sizes and densities. They are composed of “non-dense breast tissue” (otherwise known as fatty tissue) and “dense breast tissue” (comprised of milk glands, ducts and supportive tissue). What determines your breast density is the proportion of dense breast tissue you have; this greatly varies from individual to individual and may change over time. Dense breast tissue is common and is normal.

How is breast density determined?
Breast density can only be seen on a mammogram. It is not related to breast size or firmness. There are four categories of breast density:
SMP_20170809_Breast-Density-Mammogram-Illustration_V01-01.pngThese categories are listed in order of increasing density, and breasts are considered “dense” if they are in the heterogeneously dense or extremely dense categories, meaning that they have a higher proportion of non-fatty tissue.

Why is breast density important?
Dense breasts are associated with an increased risk for the development of breast cancer. However, having dense breasts does not necessarily mean that you will develop breast cancer. Density is just one of many recognized risk factors for breast cancer. For instance, increasing age is a risk factor that affects all women.
There is evidence that increased breast density may make it more difficult to detect some breast cancers on a mammogram; cancerous tissue is more difficult to detect as the breast density increases.
How can I find out my breast density category?
Complete this Request for Access to Records Form and either fax to the number provided or mail to the address on the bottom of the form. You can also drop off the form at a SMP screening centre. You will receive the requested information by mail within 3 weeks.
What should I do if I have dense breasts?
Many cancers are found on mammograms even if dense breast tissue is present. It is important to get a regular mammogram, as this is the only test proven to decrease the risk of death from breast cancer. It is also important that women notify their doctors right away if they notice any changes in their breasts, even if they have recently had a normal mammogram.  Other tests such as ultrasound and magnetic resonance imaging (MRI) are under investigation, but there are currently no provincial or national recommendations or guidelines for their use in screening.   
Women with increased breast density are encouraged to discuss their breast cancer risk with their family physician. We also encourage all women to review the modifiable risk factors for breast cancer found at: Further information regarding cancer screening may be found on our website:



SOURCE: Breast Density ( )
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