Objectives: To report an exploratory subgroup analysis assessing the extent to which the overall benefit found in the Early Prostate Cancer program is dependent on lymph node status at randomization. The program is ongoing, and the overall survival data are immature. The first combined analysis of the bicalutamide (Casodex) Early Prostate Cancer program at 3 years' median follow-up showed that bicalutamide, 150 mg once daily, plus standard care (radical prostatectomy, radiotherapy, or watchful waiting), significantly reduced the risk of objective progression and prostate-specific antigen (PSA) doubling in patients with localized/locally advanced prostate cancer.
Methods: Men (n = 8113) with localized/locally advanced disease received bicalutamide 150 mg or placebo once daily, plus standard care. The time to event data (objective progression, PSA doubling) was analyzed by lymph node status at randomization.
Results: Compared with standard care alone, bicalutamide significantly reduced the risk of objective progression, irrespective of lymph node status, with the most pronounced reduction in patients with N+ (hazard ratio [HR] 0.29; 95% confidence interval [CI] 0.15 to 0.56) compared with those with N0 (HR 0.59; 95% CI 0.48 to 0.73) and Nx (HR 0.60; 95% CI 0.50 to 0.72) disease. The largest decrease in risk of PSA doubling with bicalutamide was observed in N+ disease (HR 0.16; 95% CI 0.09 to 0.29), with significantly reduced risks seen in N0 (HR 0.45; 95% CI 0.40 to 0.51) and Nx (HR 0.38; 95% CI 0.33 to 0.44) disease.
Conclusions: The greatest reduction in the risk of objective progression and PSA doubling with bicalutamide was seen in patients with N+ disease. However, bicalutamide also provided a statistically significant benefit in those with N0 and Nx disease.