Bicalutamide monotherapy compared with castration in patients with nonmetastatic locally advanced prostate cancer: 6.3 years of followup

Purpose: Nonsteroidal antiandrogen monotherapy may be a treatment option for some patients with advanced prostate cancer. We report a survival and safety update from an analysis of 2 studies in which patients with nonmetastatic (M0) locally advanced disease were treated with either 150 mg, bicalutamide monotherapy or castration. Materials and Methods: Data from 2 open label, multicenter studies of identical design were pooled according to protocol. Patients with stage T3/4 prostate cancer were randomized to receive 150 mg. bicalutamide daily or castration (orchiectomy or 3.6 mg. goserelin acetate every 28 days) in a 2:1 ratio. Results: A total of 480 patients with locally advanced prostate cancer were randomized to treatment. After a median followup of 6.3 years mortality was 56%. There was no statistically significant difference between the 2 groups in overall survival (hazard ratio 1.05, upper 1-sided 95% confidence limit 1.31, p = 0.70) or time to progression (1.20, 1.45, p = 0.11). There were statistically significant benefits in the bicalutamide monotherapy group in the 2 quality of life parameters of sexual interest (p = 0.029) and physical capacity (p = 0.046). The highest incidences of adverse events were the pharmacological side effects of hot flashes in the castration group, and breast pain and gynecomastia in the bicalutamide group. The incidences of other types of adverse events were low. Bicalutamide was well tolerated, with few drug related withdrawals from study, and no new safety issues were identified during this longer followup. Conclusions: Monotherapy with 150 mg. bicalutamide is an attractive alternative to castration in patients with locally advanced prostate cancer for whom immediate hormone therapy is indicated.