Background: Zoledronic acid treatment reduces the incidence of skeletal-related events (SREs) in patients with bone metastases from breast, lung, and urologic cancers including prostate and renal cancer. The aim of this study was to evaluate the effect of zoledronic acid on SREs in patients with bone metastases from bladder cancer.
Patients and methods: Patients with bone metastases from bladder cancer who were receiving palliative radiotherapy were randomized to placebo or zoledronic acid (4 mg intravenous monthly) for 6 months.
Results: The patients (n = 40) were evenly distributed between the two treatment groups, and the baseline demographics of the two groups were similar. The follow-up varied from 8 to 65 weeks (median 24 weeks). Compared with patients receiving placebo, those receiving zoledronic acid had a lower mean incidence of SREs (2.05 +/- 1.0 vs. 0.95 +/- 0.9, respectively), and a larger proportion did not experience an on-study SRE (2 vs. 8 patients, respectively). Zoledronic acid also prolonged the median time to first SRE compared with the placebo (16 vs. 8 weeks, respectively). Multiple event analysis of SREs revealed that zoledronic acid decreased the risk of SRE development by 59% (hazard ratio 0.413). Zoledronic acid also increased the 1-year survival rate compared with placebo (36.3 +/- 11.2 vs. 0%, respectively). Zoledronic acid was generally well tolerated in our patient population.
Conclusions: Zoledronic acid therapy decreased the incidence of SREs and improved the 1-year survival rate of patients with bone metastases from bladder cancer, potentially through its anticancer activity.