Early bisphosphonate treatment prevents osteolytic bone lesions and enhances overall survival in Tax⁺ mice. Tax⁺ littermate mice were randomly divided into zoledronic acid–treated (0.75 μg per mouse subcutaneous injection weekly, n = 17) or saline controls (n = 12) at 1 month of age. Mice were evaluated biweekly for peripheral tumor formation, and radiographic images were taken at 3, 6, and 9 months of age. Experiments were ended when mice were 9 months old. (A) Representative radiographic images of Tax⁺ mice treated with zoledronic acid or saline at 9 months of age. Tax⁺ mice treated with saline show overt bone lesions (arrows). (B) Of the mice that developed osteolysis, numbers of tail lesions are significantly higher in saline-treated mice (P < .05). Bone lesion number is depicted as the mean ± SEM. (C) Tax⁺ mice treated with zoledronic acid were protected from the development of peripheral tumors (P < .01 by a paired t test in SigmaPlot 2001). (D) Tax⁺ mice treated with zoledronic acid show increased overall survival (P < .01 by a paired t test in SigmaPlot 2001).