Long-term oncologic outcomes of postoperative adjuvant versus salvage radiotherapy in prostate cancer: Systemic review and meta-analysis of 5-year and 10-year follow-up data

PURPOSE: To evaluate the oncologic outcomes between adjuvant radiotherapy (ART) and salvage radiotherapy (SRT) in patients with locally advanced prostate cancer or with adverse pathologic factors including positive surgical margin and high Gleason score. MATERIALS AND METHODS: We searched the literature published from January 2000 until December 2014 at MEDLINE, PubMed, Web of Science, Embase, ProQuest, and Cochrane Library. To be specific, included were studies comparing ART and SRT settings if they followed up oncologic outcomes more than 5 years. RESULTS: Overall, 3 retrospective, nonrandomized, observational studies, 1 matched control analysis, and 3 prospective randomized controlled studies met our inclusion criteria including a total of 2,380 patients (1,192 ART vs. 1,188 SRT). Higher favorable results were found in ART than in SRT was seen in the 5-year and 10-year biochemical recurrence (BCR)-free survival (risk ratio [RR], 0.61 and 0.70; 95% confidence interval [CI], 0.54-0.69 and 0.63-0.76). ART had a significantly higher 5-year progression-free survival rate than that in SRT (RR, 0.64; 95% CI, 0.51-0.80), but this was not the same for the 10-year progression-free survival rate (RR, 0.88; 95% CI, 0.72-1.08). There was no significant difference for the 5-year and 10-year overall survival rates between ART and SRT (RR, 0.80 and 0.94; 95% CI, 0.59-1.07 and 0.80-1.11). CONCLUSIONS: ART showed favorable results in BCR-free survival during the 5-year follow-up period. However, the 10-year progression-free survival and overall survival did not show any difference between ART and SRT.