Goserelin versus orchiectomy in the treatment of advanced prostate cancer: final results of a randomized trial. Zoladex Prostate Study Group

Abstract

Objectives: To compare the efficacy and safety of goserelin and orchiectomy in patients with stage D2 prostate cancer.

Methods: A randomized, open, multicenter study was conducted in 283 patients. Patients were allocated to goserelin, 3.6 mg every 28 days or to orchiectomy. Study end points were endocrine response, objective response, time to treatment failure, survival, and tolerability. Objective response was based on modified criteria of the National Prostate Cancer Project.

Results: Serum testosterone decreased from baseline to castrate levels by week 4 in each group and remained below castrate levels thereafter. Acid phosphatase and alkaline phosphatase concentrations also decreased in each group. The goserelin and orchiectomy groups had similar results for objective response (82% versus 77%) and had similar medial times to treatment failure (52 versus 53 weeks) and survival (119 versus 136 weeks). No significant interactions between treatments and prognostic factors were observed. Adjusting for baseline testosterone concentration had no effect on survival outcome. Race had no influence on outcome or efficacy end points. Common adverse events in both groups were pain, hot flushes, and lower urinary tract symptoms.

Conclusions: Goserelin is well tolerated and as effective as orchiectomy in patients with Stage D2 prostate cancer.