Significance of baseline bone markers on disease progression and survival in hormone-sensitive prostate cancer with bone metastasis

This study evaluated the baseline patient characteristics associated with the time to biochemical progression and overall survival in patients who participated in a phase II trial on zoledronic acid combined with the initial androgen-deprivation therapy for treatment-naïve bone-metastatic prostate cancer.

Patients received zoledronic acid 4 mg intravenously every 4 weeks for up to 24 months, concomitantly started with bicalutamide 80 mg orally every day and goserelin acetate 10.8 mg subcutaneously every 12 weeks.

A total of 53 Japanese patients were enrolled between July 2008 and April 2010, and 52 patients were evaluable. Median follow-up period was 41.6 months. Updated median time to biochemical progression was 25.9 months (95 % confidence interval 14.5–49.9). Higher serum bone-specific alkaline phosphatase was an independent risk factor for time to biochemical progression based on multivariate analysis (hazard ratio 6.51; 95 % confidence interval 2.71–15.62; P < 0.001). Median time to biochemical progression for patients with serum bone-specific alkaline phosphatase level higher than 26 μg/L was 12.7 months. Multivariate analysis indicated that higher serum C-terminal telopeptide of type I collagen independently increased the risk of death (hazard ratio 9.62; 95 % confidence interval 2.11–43.89; P = 0.003). Median overall survival for patients with serum C-terminal telopeptide of type I collagen level higher than 8.0 ng/ml was 31.1 months.

Baseline bone markers can be useful as predictors for disease progression and survival time in patients with bone metastasis from treatment-naïve prostate cancer treated with upfront zoledronic acid concomitantly started with androgen-deprivation therapy.