Delaying Metastatic Disease Progression In Locally Advanced Disease - Results From The Early Prostate Cancer Program At A Median Follow-Up Of 7.4 Years.

4629 Background: Progression of prostate cancer to bone metastases impacts seriously on patients (pts)’ quality of life and increases treatment costs. The 3rd analysis of the Early Prostate Cancer (EPC) program revealed that bicalutamide (CASODEX) 150 mg plus standard care (radiotherapy [RT], radical prostatectomy [RP] or watchful waiting [WW]) significantly improved progression-free survival (PFS) vs standard care alone in locally advanced disease. Adjuvant bicalutamide 150 mg also improved overall survival for RT pts with locally advanced disease. Here, we report an exploratory analysis of the effect of bicalutamide on delaying bone metastases in pts with locally advanced disease in the EPC program. Methods: The EPC program comprises 3 trials in which pts (n = 8113) were randomized to standard care plus bicalutamide 150 mg or placebo. This exploratory analysis included only pts with locally advanced disease (T3–4, any N; or any T, N+; bicalutamide n = 1367, placebo n = 1315). Distant metastases were assessed by bone scan. Metastatic PFS was defined as time from randomization to either first bone scan-confirmed progression or death in the absence of bone-scan data. A Cox proportional hazards regression model was used for the WW and adjuvant subgroups; each was analyzed separately with covariates for trial, treatment, prior therapy, baseline prostate-specific antigen level, and tumor grade. Results: At 7.4 years’ median follow-up, bicalutamide significantly improved metastatic PFS vs placebo (hazard ratio [HR] 0.64, p < 0.001 for WW; HR 0.77, p = 0.005 for RT/RP; table). The most common adverse events were gynecomastia and breast pain. Conclusion: Addition of bicalutamide 150 mg to standard care significantly reduced the risk of distant metastases in locally advanced prostate cancer, irrespective of standard care. Both the efficacy and tolerability of treatment must be considered, and therefore, bicalutamide is an option for men with locally advanced prostate cancer. [Table: see text] [Table: see text]