Adding zoledronic acid to adjuvant endocrine therapy improves disease-free survival in premenopausal breast cancer, according to a report in the Feb. 12 issue of the New England Journal of Medicine. The magnitude of the drug's beneficial effect is similar to that "for cancer therapies that in the past have caused a shift in treatment standards," said Dr. Michael Gnant of the Medical University of Vienna, Austria, and his associates. Researchers in the Austrian Breast and Colorectal Cancer Study Group's...