Hip bone density helps predict breast cancer risk

Measuring a woman’s bone mineral density (BMD) can provide additional information that may help to more accurately determine a woman’s risk of developing breast cancer, according to a new study in the journal Cancer.

Zhao Chen, MD, and colleagues at the Mel and Enid Zuckerman College of Public Health, University of Arizona in Tucson, studied approximately 10,000 postmenopausal women (average age of 63) who were part of the Women’s Health Initiative, a study conducted in 40 clinical centers throughout the U.S.

The researchers assessed the women’s initial BMD level as well as their score on the Gail risk model, which estimates 5-year and lifetime risk of invasive breast cancer for women 35 years of age or older. They then followed the women for an average of 8 years, noting which women developed breast cancer.

As expected, the study found that women with a high Gail score had a 35% increased risk of developing breast cancer, compared to women with a lower Gail score. But the study also found a 25% increase in the risk of developing the disease with each unit increase in total hip bone mineral density t-score. While the two scores were independent of each other, women with the highest scores on both assessments had a much higher risk of breast cancer.

The study results suggest that incorporating BMD tests with current risk assessments might significantly improve physicians’ ability to predict breast cancer risk in older, postmenopausal women.