Breast Density Legislation and Risk Calculations

At this point, 19 states have enacted legislation that requires breast imaging centers to inform women of their breast density. As stated in a previous blog, the obvious question for the patient and her doctors is, “Does this density increase the risk of breast cancer?” No available models handle density well (Though Tyrer Cuzick is currently validating an adjustment to their model that appears very promising) and density as a risk factor in isolation is questionable (Younger women have higher density than older women and yet have lower risk, Asians have higher density than Caucasians, and have lower risk of breast cancer).

The physician needs to determine whether genetic testing or additional imaging beyond routine mammography might be useful in the patient with dense breasts.

While risk stratification of all women is critical, it takes on added importance when the patient herself is asking you directly, “Am I at increased risk? Do I need additional evaluation or other imaging?” A quick and thoughtless answer of "No" is questionable if not dangerous. A quick answer of "Yes, you need an MRI," is also likely of marginal appropriateness. Before giving that answer, you should understand the answers to the following:

  • Does she really need an MRI?
  • Does she meet the guidelines?
  • Will her insurance carrier pay for an MRI, and if not, do you recommend that she pay out of pocket?
  • Does she need genetic testing? (If she is a BRCA1 mutation carrier, and you recommend MRI, she is at high risk of dying of ovarian cancer.)

While the impact of density on risk is open to debate, there are established guidelines for MRI and genetic testing, unrelated to density.

Relative to MRI, any woman whose lifetime risk is greater than 20% based on Tyrer Cuzick, BRCAPRO or Claus should be offered yearly MRI. In most instances, the insurance company will pay for the MRI as it is being done according to guidelines established by the American Cancer Society (ACS) and the National Comprehended Cancer Network (NCCN). On the other hand, breast density alone (In the absence of a high lifetime risk) is not considered an adequate reason to do an MRI and falls outside of guideline based care. As such, reimbursement may be problematic.

Relative to genetic testing, any woman whose risk of having a BRCA1 or BRC A2 mutation is 10% or greater by BRCAPRO, Tyrer Cuzick or the Myriad model or who meets NCCN guidelines should be counseled and offered genetic testing. These patients should be referred to the appropriate physician, nurse practitioner or counselor for a thorough evaluation and development of an individualized management strategy, not just sent for an MRI. BRCA carriers are at extremely high risk of not only breast cancer, but also of ovarian cancer. Doing MRIs and not identifying carrier status may consign a patient to death from ovarian cancer.

For example:


This patient is eligible for breast screening MRI as her lifetime risk is over 20% by Tyrer Cuzick 6 and 7, BUT she is also eligible for genetic testing based on the NCCN criteria of having a close relative with ovarian cancer. She needs genetic testing, not just MRI screening. If she tests positive, she is an appropriate candidate for oophorectomy to prevent ovarian cancer, and should be offered prophylactic mastectomy to prevent breast cancer.

For those not at elevated hereditary risk, it would be reasonable to categorize her level of risk, and then offer additional imaging appropriate to that category. Women with a 20% or greater lifetime risk by Tyrer Cuzick, BRCAPRO or Claus should be offered yearly MRI. If they cannot tolerate an MRI, then other modalities, such as whole breast ultrasound should be considered. Those between 15 and 20% lifetime risk by Tyrer Cuzick, BRCAPRO or Claus should be informed that their risk is moderate and that perhaps additional imaging might be worthwhile. As these women do not fit the guidelines for MRI, other modalities, such as whole breast ultrasound might be considered. Those less than 15% lifetime risk should be informed that their risk appears to be at the average level. Additional imaging should be at the discretion of the treating physician.

While risk stratification is critical for all female patients, it takes on added importance when the patient herself is asking you directly, “Doctor, what should I do?” It is best if that answer is based on the established guidelines.

We can help you make the models more useful. You can quickly run the various models and compare their results at CRA Health's Risk Express or go to to learn more about how our software can make identifying high-risk individuals easy and efficient. We can help you save lives.

About the Author: Kevin S. Hughes, MD, FACS


Kevin S. Hughes, MD, FACS is a co-founder and medical advisor to CRA Health. Dr. Hughes is the Massachusetts General Hospital’s Surgical Director of the Breast Screening Program, Surgical Director of the Breast and Ovarian Cancer Genetics and Risk Assessment Program, and Co-Director of the Avon Comprehensive Breast Evaluation Center, and serves as the Medical Director of the Bermuda Cancer Genetics and Risk Assessment Clinic. He is an Associate Professor of Surgery at Harvard Medical School. Dr. Hughes is actively involved in the establishment of standards and in research regarding the genetics, screening, diagnosis, and treatment of breast cancer. He is the author of numerous papers and book chapters on the subjects of breast cancer, screening, diagnosis and treatment, and risk assessment. More information can be found at: