What is Breast Density?
- The breast is made up of different tissues such as lobules, ducts, fibrous
tissues and fat.
- Some women experience denser breasts than other women due to the varying
proportions of these tissues.
- Some breasts are mostly fatty tissue and some are mostly fibrous or glandular
making them denser.
- As you age or gain weight after menopause, your breasts become less dense.
- Breast density is a very common occurrence and does not signify an abnormality.
The Four Levels of Breast Density
- Breast density is not based on how this area feels or the size but rather
how it looks on a mammogram.
- The density of your breast can only be seen in a mammogram and there are
four levels of breast density: almost entirely fatty, scattered fibroglandular
densities, heterogeneously dense, extremely dense.
- Breasts that have more fatty tissue show black in color on the mammogram
image while fibrous and glandular tissues appear white.

The Connection between Breast Density and Breast Cancer
- Women with dense breasts have a 4 to 6 time higher chance of developing
breast cancer.
- Both breast density and cancerous tissue appear white on a mammogram making
it harder to detect tumors or abnormalities.
- At this time, there is no standard measure for assessing risk for women
with dense breast tissue or any special screening guidelines or recommendations.
- Research has shown that ultrasounds and MRIs (in addition to routine mammograms)
can improve detection in women with dense breasts.
- 3D mammography (Tomo) has been shown to be 41% more accurate detecting
invasive breast cancer with 40% reduction in call backs.
- Currently, 27 states in the United States have mandatory breast density
inform laws in effect meaning your provider must send a letter if breast
density is detected.