Austrian researchers presenting at the annual San Antonio Breast Cancer Symposium discussed the results of the first large, multicenter trial to test a drug to prevent bone loss caused by other breast cancer treatments.

Bone loss is often caused by hormonal treatments like tamoxifen and goserelin in premenopausal women. Tamoxifen blocks the effects of estrogen on tumor growth, while goserelin reduces the amount of estrogen in a woman’s body.

Researchers studied 1,315 patients who received one of four treatments for their breast cancer. All patients received goserelin along with either tamoxifen, tamoxifen plus zoledronic acid, the drug anastrozole, or anastrozole plus zoledronic acid. The zoledronic acid was given as a four-milligram, 15-minute infusion every six months.

Results show patients who received hormone therapy without zoledronic acid had significant bone loss after one and two years. These patients had about a 12-percent reduction in bone loss after two years. However, patients who received zoledronic acid along with the combination therapies had stable bone mineral density with no treatment-induced bone loss.

These results, say researchers, appear to be independent of age and other risk factors. They concluded by recommending women with early-stage breast cancers should also be treated with zoledronic acid to prevent cancer treatment-induced bone loss.