Surgical versus medical castration in the treatment of metastatic prostate cancer: A systematic review and meta-analysis

Abstract

Introduction: Metastatic disease is found in up to 20% of prostate cancer (PCa) cases at diagnosis. Since their introduction in the 1980s, long acting gonadotropin-releasing hormone (GnRH) analogues, administered subcutaneously or intramuscularly every 1–6 months have widely replaced bilateral orchidectomy as the method of castration for this cohort of patients. Recent evidence suggests that surgical castration confers a superior side-effect profile and cost. We aimed to perform a systematic review and meta-analysis to compare these two treatment methods particularly in terms of survival, side-effect profile and cost-effectiveness. Methods: A systematic review of the literature was performed for studies comparing medical and surgical castration for metastatic PCa. Outcome measurements included overall survival, side-effect profile and cost. Results: Fifteen studies on 63,682 participants ( n = 59,045 for medical and n = 4637 for surgical) met inclusion criteria. Our analysis demonstrated a trend towards significance in overall survival rates in favour of surgical castration (hazard ratio = 0.89, 95% confidence interval (CI) = 0.79 to 1.01, p = 0.06), a trend towards significance in cardiovascular complications in favour of the surgical group (odds ratio (OR) = 0.79, 95% CI = 0.62 to 1.00, p = 0.05) and a significantly lower nadir prostate-specific antigen (PSA) level in favour of medical castration (MD PSA 1.17 less in medical castration group, 95% CI = 0.67 to 1.67, p < 0.01). Conclusion: Surgical castration appears to be a safe, feasible and efficacious alternative to medical castration, with evidence to suggest a potential survival benefit and limited evidence of a financial benefit in the treatment of men with metastatic PCa. Further studies are required to further quantify the financial burden of one method over another, as well as to identify which subgroup of patients respond best to each method of castration. Level of evidence: Level 1