Dense breasts have less fatty tissue and more non-fatty tissue compared to breasts that aren't dense. One way to measure breast density is the thickness of tissue on a mammogram. Another categorizes breast patterns into four types depending on which type of tissue makes up most of the breast. Still, no one method of measuring breast density has been agreed upon by doctors. Breast density is not based on how your breasts feel during your self-exam or your doctor's physical exam. Dense breasts have more gland tissue that makes and drains milk and supportive tissue (also called stroma) that surrounds the gland. Breast density can be inherited, so if your mother has dense breasts, it's likely you will, too.
Research has shown that dense breasts:
- can be 6 times more likely to develop cancer
- can make it harder for mammograms to detect breast cancer; breast cancers (which look white like breast gland tissue) are easier to see on a mammogram when they're surrounded by fatty tissue (which looks dark).
Steps you can take
If you have dense breasts, there lifestyle choices you can make to keep your breast cancer risk as low as it can be:
- maintaining a healthy weight
- exercising regularly
- limiting alcohol
- eating nutritious food
- never smoking (or quitting if you do smoke)
These are just a few of the steps you can take. Review the links on the left side of this page for more options.
Along with lifestyle options, many doctors recommend additional screening for women with dense breasts. This might include MRI scanning and ultrasound.
More frequent screening: If you have a higher risk of breast cancer because you have dense breasts, you and your doctor will develop a screening plan tailored to your unique situation. General recommended screening guidelines include:
- a monthly breast self-exam
- a yearly breast exam by your doctor
- a digital mammogram every year starting at age 40
Digital mammography is better than film mammography in women with dense breasts, regardless of age.
Your personal screening plan also may include the following tests to detect any cancer as early as possible:
- MRI (magnetic resonance imaging) of the breast
Talk to your doctor about developing a specialized program for early detection that meets your individual needs and gives you peace of mind.
To improve the information learned from your breast imaging studies, it's important to both compare this year's study to prior years' studies and to correlate the information learned from the various imaging studies obtained (what you feel in the breast, compared to the results of your mammogram, MRI, and ultrasound). Usually test reports will say if the recent imaging test is different from other tests or prior results of the same test. Obtaining a copy of each breast imaging report and putting them in a binder keeps you in the loop and reduces the risk of your tests falling through the cracks or someone missing an important finding.
Think Pink, Live Green: A Step-by-Step Guide to Reducing Your Risk of Breast Cancer teaches you the biology of breast development and how modern life affects breast cancer risk. Download the PDF of the booklet to learn 31 risk-reducing steps you can take today.