5 Facts to Know
- Breast density is determined through a woman’s mammogram and described as one of four categories depending on the amount of breast tissue in comparison to fat in the breast.
- 40% of women age 40 and over have dense breasts.
- Cancer is 4 times more likely in women with extremely dense breasts than in women with fatty breasts.
- Though mammograms find some cancers not seen on other screening tests, in dense breasts, mammograms will miss up to 40% of cancers present. As density increases, the effectiveness of mammography decreases.
- Other screening tests, such as ultrasound or breast MRI, in addition to mammography substantially increase detection of early stage breast cancers in dense breasts.
Dense Breast Tissue Categories
(A) Fatty; (B) Scattered fibroglandular density; (C) Heterogeneously dense; (D) Extremely dense
How do you answer the question “Are you dense?” Breasts which are (C) heterogeneously dense, or (D) extremely dense on mammography, are considered “dense breasts.”