Breast Density
The News
On March 28th the FDA proposed adding a new requirement for
- Breast density reporting to both patients and referring health providers.
- Currently Arizona and 36 other states require some level of breast density notification after a mammogram
- So this is will not change anything for women in Arizona
What does dense breasts mean?
- Breasts contain glandular, connective, and fat tissue. Breast density is a term that describes the relative amount of these different types of breast tissue as seen on a mammogram.
- Dense breasts have relatively high amounts of glandular tissue and fibrous connective tissue and relatively low amounts of fatty breast tissue.
- Nearly half of all women age 40 and older who get mammograms are found to have dense breasts.
- Breast density is classified into four categories:
- Almost entirely fatty breast tissue, found in about 10% of women
- Scattered areas of dense glandular tissue and fibrous connective tissue (scattered fibroglandular breast tissue) found in about 40% of women
- Heterogeneously dense breast tissue with many areas of glandular tissue and fibrous connective tissue, found in about 40% of women
- Extremely dense breast tissue, found in about 10% of women
- Breast density decreases with age
Why are dense breasts important?
- This can make a mammogram harder to read and may make it more difficult to find breast cancer in women with dense breasts.
- Women with dense breasts have a higher risk of breast cancer than women with fatty breasts, and the risk increases with increasing breast density but not all women with dense breasts will go on to develop breast cancer.
- Research has found that breast cancer patients who have dense breasts are no more likely to die from breast cancer than breast cancer patients who have fatty breasts, after accounting for other health factors and tumor characteristics.
- Some states now require that women with dense breasts be covered by insurance for supplemental imaging tests.
What to do about dense breasts?
- Increased testing?? (3D mammogram, ultrasound, MRI)
- 37 states require density notification but only 7 states have laws requiring insurance coverage for additional testing
- The value of supplemental, or additional, screening tests such as ultrasound or MRI for women with dense breasts is not yet clear.
- United States Preventive Services Task Force. Ongoing clinical trials are evaluating the role of supplemental imaging tests in women with dense breasts.
Remaining Questions
- Why do some women with dense breasts go on to develop breast cancer, while others do not? Can biomarkers be identified that help predict whether breast cancer will develop in a woman with dense breasts?
- Can imaging tests such as 3-D mammography (breast tomosynthesis), MRI, and ultrasound help provide a clearer picture of breast cancer risk for women with dense breasts?
- Are there certain patterns or areas of dense breast tissue that are particularly “risky”?
- Are changes in breast density over time associated with changes in breast cancer risk?
- Are there additional treatments or lifestyle changes for women with dense breast to reduce their breast risk?
Remaining Need
A screening strategy that better identifies women at high risk and a treatment to reduce that risk before cancer occurs (pap/LEEP for cervix cancer; colonoscopy/polypectomy for colon cancer).
