One June 1, 2015, Michigan became the twenty-first state to enact the breast density notification law, which requires physicians to share information with patients about breast density data in a mammogram report. This information may help some woman detect cancer earlier.
How does this new law affect me?
The new law requires women to be notified after their mammogram if they have dense breast tissue. The law was put into place so that women and their physicians can have a better conversation about the risks and benefits of additional screening.
What is breast density?
Normal breasts are composed of different types of tissues. Dense breasts have more fibrous and glandular tissue; low-density breasts are composed of more fatty tissue. Dense breasts are normal and common. Approximately 50 percent of women over the age of 40 have dense breast tissue.
How can I tell if my breasts are dense?
Breast density is determined by the radiologist who reads your mammogram. A mammogram is an X-ray of the breast. Breast density is not a measure of how breasts feel (lumpy or firm) and can only be determined by X-ray.
Why is breast density important?
There are four categories used by the radiologist to describe the various types of breast tissue:
- almost all fatty tissue
- a mixture of fat and glandular tissue
- heterogeneously dense tissue
- extremely dense tissue
Women with category 1 or 2 tissue are considered fatty and women with category 3 or 4 are considered dense. Dense breast tissue may increase your risk for breast cancer, because the various types of breast tissues show up differently on a mammogram. X-rays pass through fatty tissue and so they appear as darker areas. Fibrous and glandular tissue block X-rays and therefore they appear as white areas on the film. Breast tumors can also look white on the film. Since dense breast tissue sometimes looks the same on an X-ray as a tumor, it can be more difficult to identify a cancer.
Do I still need a mammogram?
Yes. Mammography is the only screening tool that has been proven to lower your risk for breast cancer mortality. Even if your breasts are dense, a mammogram can still be beneficial in finding the cancer early. It is important for you to continue to get your regular mammograms.
My breasts are dense, now what?
Discuss it with your doctor and don't be afraid to ask questions.
Your doctor can use this information to determine whether other supplemental imaging tests, in addition to your mammogram, may be appropriate for you. There are many considerations involved in determining your risk for breast cancer. The more information you know, the better equipped you are to determine your individual risk and make the choices that are right for you. The most important thing to remember is that regular screening with mammography, and if appropriate, with supplemental imaging, saves lives. Most major organizations support the notion that informed decision-making should be made by the patient after she has had a detailed discussion with her health care provider regarding all her risks for breast cancer.