The U.S. Researchers, in a new study, found a connection between high bone mineral density (BMD) and increased chances of developing breast cancer in postmenopausal women. The study, undertaken by Dr. Zhao Chen from the University of Arizona, Tucson, examined Gail scores and hip BMD data in postmenopausal women. Gail scores use information such as family history, reproductive history, age, race, as well as history of breast biopsies to try to estimate the risk of breast cancer developing over a five year and lifetime period.

The results of the study indicated that combining BMD tests with other standard tests like the Gail model could help improve the doctor’s ability to forecast breast cancer risks in older women. These results are corroborated by an earlier study presented during the American Society of Clinical Oncology annual meeting in May which discovered that a drug Zometa, used to treat osteoporosis reduced breast cancer risks in postmenopausal women.

The researchers in the recent study examined 9941 older women’s risk factor for breast cancer. Over an average time period of 8.43 years, 327 women developed breast cancer.  They found women who had a high Gail risk score had a 35 percent increased risk for developing breast cancer as compared to women with a lower Gail risk score. They also found with each unit increase in hip BMD, a 25 percent increase in breast cancer risk.

Dr. Chen and colleagues suggest, "Future studies should investigate whether incorporating BMD and Gail score with other risk factors, such as breast density, can further improve the identification of women at high risk for developing breast cancer."

 Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La, says women who have higher bone density are usually overweight or obese, and it seems that such conditions increase the risk of breast cancer.

Another study done earlier this year showed a connection between women with breast cancer who have vitamin D deficiencies having a higher chance of disease recurrences and even dying from the disease.

Despite the many studies done, experts feel there is scope for more. Dr. Mary Daly, director of the Cancer Prevention and Control Program at the Fox Chase Cancer Center in Philadelphia, feels the true connection between estrogen, bone density and cancer still need to be cleared up.