The issue of breast density has gained increasing attention in the past several years, and to date, 12 states have enacted density-reporting laws. While the issue can be confusing and a bit scary for women, being informed about breast density, its potential impact on breast cancer and options for additional screening can help women better understand what it really means.
Breast density is important because it can make breast cancer more difficult to detect. Although Arizona does not yet have legislation requiring patients to be notified of their breast density, Northern Arizona Radiology is taking the lead in providing notifications to its patients.
Radiologists have routinely reported breast density to patients’ referring physician for years. However, up until now, it has not been a part of the standard results letter that women receive if their mammogram is negative.
By including breast density in our patients’ mammogram, the patient is now aware that while her mammogram is negative, having dense breast tissue might make it more difficult to detect cancer. This allows the woman to discuss the pros and cons of additional screening options with her physician; it’s a balanced, informed approach.
According to the American College of Radiology (ACR), about 40 percent of all U.S. women – approximately 40 million – are considered to have dense breasts, and women with dense breast tissue have an increased risk of developing breast cancer. The Susan G. Komen Foundation Risk Factors and Prevention Guide cites clinical studies showing women with dense breast tissue are up to five times more likely to get breast cancer compared to women with low breast density.
Ward explained that dense breasts are less fatty and have more connective tissue, which appears white like tumors, and therefore may be more difficult to detect.
While breast density is completely normal and is just one of many factors, it is an important one and can impact risk. However, it hasn’t yet been linked to an overall increase in the risk of death from breast cancer.
The ACR classifies breast density into four categories:
- Almost entirely fatty (low density) – about 10 percent of women have fatty breast tissue.
- Scattered areas of density (somewhat dense) – about 40 percent of women have somewhat dense breast tissue.
- Heterogeneously (uniformly) dense – about 40 percent of all women have dense breast tissue.
- Extremely dense – about 10 percent of women have very dense breast tissue.
Having dense breasts plus one or more additional risk factors for breast cancer may justify the need for supplemental screening after mammography.
Supplemental screening at NAR includes breast MRI, breast specific gamma imaging (nuclear imaging with a specialized camera and tracer injection) and breast ultrasound. When used in conjunction with mammography, such tests may find hidden cancer, leading to improved early detection. FBN
Stephen V. Ward, M.D., is a board-certified radiologist at Northern Arizona Radiology.