Introduction

Retrospective studies comparing outcomes of radical prostatectomy (RP) versus radiotherapy (RT) for patients with clinically localized prostate cancer (PCa) have conflicting conclusions and are limited by methodological biases arising from distinct baseline patient and cancer features. We used propensity score-matched analysis and consequent competing risk regression analysis to compare cancer-specific mortality (CSM) and other-cause mortality (OCM) outcomes of RP versus RT ± androgen deprivation therapy (ADT).

Methods

The multi-center Severance Urological Oncology Group PCa registry was utilized to identify 3,028 consecutive patients with localized PCa treated by RP (n=2,521) or RT±ADT (n=507) between 2005 and 2016. 339 RT±ADT cases were matched with an equal number of RP cases by propensity scoring based on patient age, preoperative prostate-specific antigen, biopsy Gleason score, clinical tumor stage, and Charlson Comorbidity Index (CCI). Competing risk regression analysis was used to evaluate CSM and OCM during the median follow-up of 68.9 months.

Results

Five-year OS rates for patients treated with RP and RT±ADT were 94.7% and 92.6%, respectively (p=0.105). Both treatments conferred comparable metastasis-free survival (p=0.778) and progression to CRPC survival (p=0.071), respectively. Cumulative incidence estimates revealed comparable CSM rates following both treatments within all NCCN risk groups (p=0.155). Gleason score ≥8 was associated with higher risk of CSM (HR=8.107, 95% CI 1.676-39.21; p=0.009). OCM rates were comparable between both treatment groups in the low and intermediate risk categories (p=0.354 and p=0.643, respectively). For high risk patients, RT±ADT was associated with higher OCM rates compared to RP (13.9% vs. 4.3%; p=0.001). Predictors of OCM were age ≥75 years (HR=2.382, 95% CI 1.363-4.164; p=0.002) and CCI ≥2 (HR=3.244, 95% CI 1.731-6.084; p<0.001).

Conclusions

RP and RT±ADT provide comparable CSM outcomes for all localized risk group patients with PCa. The risk of OCM should be cautiously considered when making treatment decisions for old aged high risk patients with significant comorbidities.

Funding

none