Objective: To conduct a meta-analysis of the randomized controlled trials (RCTs) comparing adjuvant radiotherapy (ART) to wait-and-see (WS) strategy in pathologic T3 or margin-positive prostate cancer.
Methods: A comprehensive EMBASE, MEDLINE, http://www.clinicaltrails.gov, and Cochrane Library search for RCTs of ART versus WS was done. Results were synthesized for metastasis-free, biochemical progression-free, clinical progression-free, hormone-free, and overall survival as well as gastrointestinal (GI) and genitourinary (GU) toxicities. Either random-effects model or fixed-effects model were used based on the test of heterogeneity.
Results: Three RCTs (EORTC22911, SWOG8794, ARO96-02/AUO-AP09/95) were identified with 1737 patients. ART resulted in greater biochemical progression-free survival (hazard ratio [HR]=0.48, P<0.00001) including benefit in all subsets, greater clinical progression-free survival (HR=0.73, P=0.0003) including benefit in subsets with margin-positive or seminal vesicle invasion and, greater hormone-free survival (HR=0.64, 95% confidence interval, 0.51-0.80, P=0.0001). Ten-year metastasis-free survival was significantly improved with ART (odds ratio=0.77, P=0.02). There was no survival benefit (HR=0.97; P=0.89). With ART compared with WS, there was significantly increased toxicity of any grade (50% vs. 38.6%), grade 2 or greater GU toxicity (17.1% vs. 10.3%), grade 2 or greater GI toxicity (2.5% vs. 1.1%), urinary stricture rates (11.1% vs. 5.7%) and, urinary incontinence (6.9% vs. 2.7%).
Conclusions: Ten-year metastasis-free survival is significantly improved with ART compared with WS. Biochemical progression-free, clinical progression-free, and hormone-free survival were also improved with ART. Grade 2 or higher GI and GU toxicities were greater in ART. Therefore, ART should be offered to patients with these high-risk features.