Systematic review and meta-analysis of trials evaluating the role of adjuvant radiation after radical prostatectomy for prostate cancer: Implications for early salvage

  • Bimal Bhindi Department of Surgery, Section of Urology, University of Calgary, Calgary, AB, USA
  • Soum D. Lokeshwar Miller School of Medicine, University of Miami, Miami, FL, USA
  • Zachary Klaassen Georgia Cancer Center, Augusta, GA
  • Laurence Klotz Division of Urology, Department of Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
  • Christopher J.D. Wallis Department of Urology, Vanderbilt University Medical Center, Nashville, TN, USA
Keywords: Adjuvant radiotherapy, Prostatectomy, Prostatic neoplasms

Abstract

Introduction: Recent reports suggest that early salvage radiation (esRT) is non-inferior to adjuvant radiation (aRT) for adverse pathological features at radical prostatectomy. However, aRT was accepted as a standard treatment primarily based on effects on biochemical progression-free survival (bPFS). In order to understand the merits of esRT, the objective was to reassess if aRT vs. observation is associated with improved overall survival (OS).

Methods: A systematic review and meta-analysis of published randomized trials evaluating aRT was performed. The primary outcome was OS. Secondary outcomes were metastasis-free survival (MFS), loco-regional recurrence-free survival (RFS), bPFS, and adverse events. We performed a random-effects meta-analysis.

Results: Four randomized trials including 2068 patients with a median followup of 8.7–12.6 years were identified. While all trials reported a bPFS benefit, only one reported an OS benefit. Upon meta-analysis, no significant OS benefit was detected with aRT vs. observation (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.61–1.33), although consistent bPFS (HR 0.47, 95% CI 0.41–0.54) and local-RFS (HR 0.54, 95% CI 0.39–0.73) benefits were noted. There is an uncertain MFS benefit with aRT (HR 0.79, 95% CI 0.62– 1.01), and the effect is largely driven by one trial with a notable risk of bias. There was also a risk of overtreatment, with 35–60% of patients being biochemical recurrence-free with observation alone. Adverse events risk was greater with aRT vs. observation.

Conclusions: Although aRT vs. observation provides a bPFS benefit related to local control, there is no clear OS or MFS benefit, a greater risk of adverse events, and a risk of overtreatment. By extension, these data have implications for patient selection and counselling for esRT.

Published
2020-05-12
How to Cite
Bhindi, B., Lokeshwar, S. D., Klaassen, Z., Klotz, L., & Wallis, C. J. (2020). Systematic review and meta-analysis of trials evaluating the role of adjuvant radiation after radical prostatectomy for prostate cancer: Implications for early salvage. Canadian Urological Association Journal, 14(10), 330-6. https://doi.org/10.5489/cuaj.6440
Section
Original Research