Screening mammography has been a topic of debate in breast cancer diagnostics due to a shifting consensus (or lack thereof) over the age women benefit most from having the test (OT 3/10/14 issue). But new findings from a group of breast imaging experts, cardiologists, and internists bring a whole new variable to the equation.
The researchers found that breast arterial calcification, as assessed by digital mammography, is a strong predictor of coronary artery calcification-and is a superior predictor of women at high risk of cardiovascular disease compared with other standard risk factors, according to their study presented at the American College of Cardiology Annual Scientific Session last month and recently published in the Journal of the American College of Cardiology Cardiovascular Imaging (2016;9:350-360).
"Mammograms can serve a dual function," the study's lead author Laurie Margolies, MD, FACR, Associate Professor of Radiology at Icahn School of Medicine and Director of Breast Imaging at Dubin Breast Center at Mount Sinai Hospital, explained in an email.
"The same mammogram exam can screen for breast cancer and look for evidence of cardiovascular disease. This dual function can be accomplished without additional radiation to the patient; the patient's mammogram would not take any longer; and it would add only seconds to the interpretation and reporting time for the breast radiologist," she said.
For the study, Margolies and her colleagues screened 292 women using both digital mammography and nongated computed tomography, and then compared how closely the breast artery calcification scores were related to the coronary artery calcification score. The data showed a sensitivity of 63 percent, a specificity of 76 percent, a positive predictive value of 70 percent, a negative predictive value of 69 percent, and an accuracy of 70 percent.
While additional confirmatory data would be necessary to make recommendations on cardiac risk assessment, the authors note in the study, "The opportunity to significantly improve the identification of high-risk women by further simple analysis of a broadly used screening tool should be intensively evaluated in larger patient cohorts."
Here's what Margolies said cancer care providers should know about the research.
1 Could you elaborate on why these findings suggest mammograms might also be useful in identifying women at risk for cardiovascular disease?
"A key finding in this study is that breast arterial calcification is a very strong independent risk factor for the presence of coronary artery calcification-more significant than age or hypertension. And there is actually a strong quantitative correlation between breast and coronary artery calcification.
"When the information about breast arteries is added to traditional risk evaluation, its significance is even greater. The positive predictive value of about 70 percent is as good as Framingham Risk Scores or the 2013 Cholesterol Guidelines Pooled Cohort Equations for identification of women at high risk of cardiovascular disease."
2 Is this the first evidence that mammography might play a role in predicting heart health? Is the evidence sufficient to suggest mammograms can or should be used for more than just diagnosing breast cancer?
"Breast arterial calcification has been the subject of previous research, and most studies have shown a correlation of breast arterial calcification with myocardial infarction, stroke, and other cardiovascular diseases. As Drs. Nasir and McEvoy note in their editorial accompanying this research (J Am Coll Cardiol Img 2016;9:361-363), the reporting of breast arterial calcification has not though been incorporated into reporting guidelines and health care delivery protocols."
3 What should practicing oncologists know about the findings from this research?
"Cancer care providers should know that there is a strong correlation between breast arterial calcification and cardiovascular disease. This suggests that women who have breast arterial calcification might benefit from further testing such as gated formal cardiac calcification scoring and/or preventative treatments such as diet modification, exercise, smoking cessation, medication, or other strategies. Practicing oncologists can and should incorporate breast arterial calcification data into their patients' overall treatment plans.
"Primary care physicians and others receiving mammography reports do, however, need education about the linkage of breast and systemic arterial calcification. And this study will hopefully add momentum to the increasing awareness and discussion of women's cardiac health."