A popular type of osteoporosis drug may reduce women's risk of developing breast cancer, according to two studies released at the San Antonio Breast Cancer Symposium.
Researchers analyzed data from a large NIH study and found that women taking drugs like Fosamax, Boniva and Zometa had almost a third fewer cases of breast cancer compared with those who weren't on the drugs. In a second study of 4,500 postmenopausal women, those who were on bisphosphonates for five or more years experienced 30 percent fewer cases of breast cancer than non-users.
Experts are optimistic, but cautious, about the two study results. They point out that while the data looks promising, the two studies weren't specifically designed to compare the rate of breast cancer in bisphosphonates users versus those not on the drugs. Without a properly structured study, physicians are hesitant to recommend the drugs, which can cause bone and muscle pain. "For women who need treatment for osteoporosis, these data suggest that there may be some secondary gain," Harold Burstein, breast oncologist at Dana-Farber Cancer Institute in Boston, told ABC News. "However, the data are not sufficient to suggest that bisphosphonate therapy would prevent breast cancer for ordinary women." But the researchers' findings do warrant a new study of bisphosphonates potential anti-cancer benefits.