Dense Breast Tissue Should Not Be Ignored

Dense Breast Tissue Should Not Be Ignored

New “Patient Inform” Law

Women in Virginia are becoming more aware of a health issue that can come to light during their annual mammograms. Thanks to the efforts of a committed group of breast cancer advocates that included a local breast cancer survivor, this July Virginia became the third state in our country to mandate that facilities and physician offices performing mammography services notify patients when dense breast tissue is found. In these cases, patients should receive a letter saying they may have dense breast tissue and their referring physicians will receive a report with their full mammography results.

What is Dense Breast Tissue?

Breast density is determined by the relative proportion of glandular and connective tissue to fatty tissue in the breast. It is commonly reported as a percentage with anything over 50 percent considered dense. Women with greater than 75 percent breast density have an even higher risk and should be offered other studies to supplement their mammogram.

Why It's Important

Dense breast tissue can make cancer and other abnormalities more difficult to detect and increase the likelihood some issues will be entirely missed. While not a common occurrence, a small percentage of women have been diagnosed with late-stage breast cancer after years of clear mammograms because their cancer was not discovered in dense breast tissue.

This type of tissue may even be a precursor to cancer. According to the National Cancer Institute at the National Institutes of Health in Bethesda, women who have a high percentage of dense breast tissue have a higher risk of breast cancer than women of similar age who have little or no dense tissue in their breasts.

Breast density is not based on family history and cannot be determined by look and feel of the breast. This makes mammograms incredibly important in identifying patients who are at risk. Approximately 75 percent of women in their 40s have dense breasts. This percentage typically decreases with age - with 54 percent of women in their 50s and 42 percent of women in their 60s having dense breasts. Overall, breast density decreased approximately 2 percent per year with the greatest drop occurring at menopause.

Patient Strategies

While the new patient letter does not offer options or clarity on how to deal with a diagnosis of dense breast tissue, there are several steps a patient can take to learn more.

First, a patient should schedule a follow-up appointment with her referring physician. During the visit, she should discuss potential increased risks and whether additional screening is needed.

Ultrasound is a readily available and reliable imaging method to screen patients with increased density. It does not emit radiation and can generate clear images of dense breast tissue, making it a great adjunct to mammograms in high-risk patients. Ultrasound technology is improving all the time and unlike other forms of breast imaging, it is becoming less expensive and, therefore, more available. It also is the only test that can be used real time in conjunction with a clinical exam to explore dense tissue. No radiation means patients can be screened at younger ages, during pregnancy and more frequently if needed.

Mammography for women with dense breast tissue is very important with 3D mammograms (also known as tomosynthesis) now the latest and most advanced technique. 3D mammography improves the ability to image dense tissue and is capable of finding cancers at an earlier stage. Inova Mount Vernon Hospital implemented 3D mammography earlier this month and is the first and only Inova facility to offer this technique.

When other risk factors for breast cancer are present, an MRI should also be considered. While expensive and often difficult to have approved by insurance, MRI in patients who are documented to have a higher lifetime risk of breast cancer is a valuable tool.

Additional Resources

For patients interested in conducting additional research, I recommend visiting websites for the National Cancer Institutes ( and a nonprofit organization dedicated to the density issue called Are You Dense (

For years, increased breast density has been recognized as a challenge in screening patients for breast cancer. Now that we know the full impact of dense tissue, we have to change our view of patients with dense tissue from that of frustration to a call to action.

Every woman who has a mammogram needs a discussion about their breast density and a screening process that is customized to their needs. It can be a fairly involved process for some, but we need to be using the right tools for the right patients to get the best results.