The issue of breast density has been a hot topic over the last several years. Many women are told they have “dense breasts” when they have their mammograms, but most are not sure what they are supposed to do about it.
First, let me define exactly what Breast Density means.Breast density refers to the fibrous and glandular tissue that appears on a woman’s mammogram. For some, it is not an issue, as they may have very little density seen on the mammogram. For others, their breasts may have a very high density level. Dense tissue on a mammogram is white, just as a benign or cancerous lump can show up as white. The analogy that is often made is trying to find a snowball in a blizzard. The higher the breast density level the more intense the “blizzard” is. This does not always mean that women with dense tissue will have more lumps or breast symptoms, like pain, etc. Breast density is strictly a mammographic image finding, and not a physical exam finding or symptom.
So why the fuss? Not only does dense tissue make it harder to see changes on mammogram that could be a cancer, higher breast density leads to a 4 to 6-fold increase risk of developing breast cancer. Mammograms may end up missing up to 40% of breast cancers in women with dense tissue, according to the American Cancer Society. In Dallas in 2009, a woman named Henda Salmeron was told she had dense breast tissue, and ultimately developed a breast cancer that was not detected on her mammogram. After undergoing surgery and treatment for her cancer, she was determined to do something about this. She contacted her state representative and convinced him to take action. Eventually, “Henda’s Law” was passed in 2011 in Texas and Connecticut, which mandates that imaging centers and radiologists report about a woman’s increased breast density. This allows the patient the ability to discuss this finding with her doctor and formulate a plan based on any established risk factors. More imaging or tests may be necessary in some cases. Currently 20 states have enacted this law, with many more soon to enact the law.
From a clinical perspective, increased breast density can be a surrogate marker for proliferation of breast tissue. In other works, it may indicate a much “busier” breast with more potential for cancer risk. Dense areas on mammograms make detection of cancer more difficult, but bear in mind that not all dense findings are a concern for cancer. Highly trained breast radiologists are best suited to determine which dense areas are cause for concern. And there are other tools that can help in this situation. One example is 3-D Mammography, which generates a much more detailed image of the breast, using reconstructed 2 dimensional images. Ultrasound is another tool that can greatly aid in cases of increased breast density, and many centers are utilizing very sophisticated sonographic imaging in these cases.
In my practice, in the case of dense breast tissue, I review the mammogram with the radiologists thoroughly, and together with the patient, carefully formulate a plan of action based on the report and the patient’s own risk factors. Involving the patient with this plan of action is very important, in my opinion. Ultimately, having dense breast tissue does not mean a patient will certainly develop breast cancer. But the more we know about the benefits and limitations of imaging tools, the better advocates we can be for our patients.