What kind of breasts do you have We’re not talking about size, we’re talking about density. Almost half of all women over 40 who get mammograms have dense breasts, which means there is a lot of fibrous or glandular tissue and not a lot of fat in the breasts. Glandular tissue produces breast milk, while fibrous tissue and fat shape the breasts.
Don’t know if you have thick breasts? You’re not alone. In a survey, only 58% of women who responded had heard of breast density and only 49% knew it could affect breast cancer detection.
Why Could Breast Cancer Be Overlooked? Well the problem is that fibroglandular (dense) tissue appears white on a mammogram, but so does cancer. Therefore, it is more difficult to detect tumors in women with dense breasts by mammography alone than in women with non-dense breasts. Therefore, the American Society of Breast Surgeons recommends that additional imaging such as breast MRI or ultrasound be considered in addition to annual mammograms for women with dense breasts and for women with a personal history of breast cancer and dense breasts, the American College of Radiology (ACR ) recommends an annual breast MRI.
Women with dense breasts are more likely to develop breast cancer than women with non-dense breasts, and the risk increases as breast density increases. A study of cancer risk in more than 200,000 women aged 40 and over found this to be one of the most common risk factors in women before and after menopause. This is one of the reasons why, in 2019, Congress directed the U.S. Food and Drug Administration to establish a minimum standard for including breast density information in mammography reports. The updates are still in development and have not yet been completed.
Most states and the District of Columbia require some notification of breast density in patients after a mammogram. (See if your state is one of them here.)
Understand breast density
The American College of Radiology uses the Breast Imaging Reporting and Data System (BI-RADS) assessment method to determine the degree of density:
ONE – Less than 25% dense breast tissue and found in approximately 10% of women.
B. 26% to 50% of the dense breast tissue known as “scattered fibroglandular breast tissue” found in approximately 40% of women.
C. – Fifty-one percent to 75% of dense breast tissue, called “heterogeneous dense breast tissue,” found in approximately 40% of women
D. – More than 75% of dense breast tissue, called “extremely dense breast tissue”, and found in approximately 10% of women.
Women, especially women with dense breasts, should have a risk assessment interview with their health care provider (HCP). There are several validated risk assessment models that take into account different combinations of factors such as age, biometrics, reproductive factors, breast density, family history, and ethnicity, and that can provide an estimate of a woman’s individual risk of developing breast cancer compared to women at average risk. If your calculated risk is increased, you should discuss with your doctor how to reduce your risk and do additional health screening.
Risk assessment tools play an essential role in determining your screening needs. This is important because most women with heterogeneously dense breasts and no family history have only a slightly increased risk of breast cancer and do not need additional screening. If your lifetime risk is over 20% according to current guidelines, the ACR recommends screening with breast MRI in addition to mammography.
The first step in understanding breast density is simple. Check with your radiologist or other handicapped person if you have thick breasts. If you do, make an appointment to talk about how dense breasts contribute to your overall risk for breast cancer, how you can reduce that risk, and whether you might need additional screening beyond a mammogram. It is important to always remember to speak to your HCP about all of your health needs.
This resource was created with the support of Bayer.