There are four categories of breast density as determined by a mammogram. The radiologist assigns each mammogram to one of the categories. Your doctor should be able to tell you whether you have dense breasts based on where you fall on the density scale.
Having dense breast tissue may increase your risk of getting breast cancer. Dense breasts also make it more difficult for doctors to spot cancer on mammograms. Dense tissue appears white on a mammogram (See Heterogeneously and Extremely Dense Examples Below). Lumps, both benign and cancerous, also appear white. So, mammograms are less accurate in women with dense breasts.
Knowing your breast density is important so you can make appropriate decisions on when and how you will be screened for breast cancer. Women, especially with family histories of breast cancer or that have had sudden changes in their breasts should be evaluated before age 30. Routine self exams are very important, changes in the size or shape should always be monitored. If you have dense breasts when and how should you be screened for breast cancer?