Surgery Versus Radiotherapy for Clinically-localized Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT: To date, there is no Level 1 evidence comparing the efficacy of radical prostatectomy and radiotherapy for patients with clinically-localized prostate cancer. OBJECTIVE: To conduct a meta-analysis assessing the overall and prostate cancer-specific mortality among patients treated with radical prostatectomy or radiotherapy for clinically-localized prostate cancer. EVIDENCE ACQUISITION: We searched Medline, EMBASE, and the Cochrane Library through June 2015 without year or language restriction, supplemented with hand search, using Preferred Reporting Items for Systematic Reviews and Meta-Analysis and Meta-analysis of Observational Studies in Epidemiology guidelines. We used multivariable adjusted hazard ratios (aHRs) to assess each endpoint. Risk of bias was assessed using the Newcastle-Ottawa scale. EVIDENCE SYNTHESIS: Nineteen studies of low to moderate risk of bias were selected and up to 118 830 patients were pooled. Inclusion criteria and follow-up length varied between studies. Most studies assessed patients treated with external beam radiotherapy, although some included those treated with brachytherapy separately or with the external beam radiation therapy group. The risk of overall (10 studies, aHR 1.63, 95% confidence interval 1.54-1.73, p<0.00001; I(2)=0%) and prostate cancer-specific (15 studies, aHR 2.08, 95% confidence interval 1.76-2.47, p < 0.00001; I(2)=48%) mortality were higher for patients treated with radiotherapy compared with those treated with surgery. Subgroup analyses by risk group, radiation regimen, time period, and follow-up length did not alter the direction of results. CONCLUSIONS: Radiotherapy for prostate cancer is associated with an increased risk of overall and prostate cancer-specific mortality compared with surgery based on observational data with low to moderate risk of bias. These data, combined with the forthcoming randomized data, may aid clinical decision making. PATIENT SUMMARY: We reviewed available studies assessing mortality after prostate cancer treatment with surgery or radiotherapy. While the studies used have a potential for bias due to their observational design, we demonstrated consistently higher mortality for patients treated with radiotherapy rather than surgery.