Adjuvant Radiation Therapy After Radical Nephrectomy in Patients with Localized Renal Cell Carcinoma: A Systematic Review and Meta-analysis

Context: Adjuvant radiation therapy has been recommended for patients at higher risk of relapse from renal cell carcinoma (RCC) to improve disease-free survival (DFS) and overall survival (OS) after radical nephrectomy. Objective: To quantify the benefit of adjuvant radiation therapy. Evidence acquistion: A systematic review of electronic databases identified pub- lications exploring the association between adjuvant radiation therapy and locoregional recurrence (LRR), DFS, and OS among patients after radical nephrectomy for early-stage RCC. Hazard ratios for DFS were weighted and pooled using the generic inverse variance and random effects model. Odds ratios for LRR, DFS, and OS at 5 yr were weighted and pooled in a meta-analysis using Mantel-Haenszel randomeffects modeling. Evidence synthesis: Twelve studies comprising 1624 patients were included in the analysis. Ten studies were retrospective and two were randomized controlled trials. Adjuvant radiation therapy was delivered to 37% of patients. The median follow-up was 49 mo. Adjuvant radiation therapy was not associated with better DFS or OS at 5 yr, but was associated with less LRR. Conclusions: With the caveat that confounding by indication may result from pooling data from predominantly nonrandomized studies, adjuvant radiation after radical nephrectomy was not associated with improved DFS or OS but was associated with less LRR. Patient Summary: Radiation therapy after resection of renal cell carcinoma with a high risk of relapse may reduce the risk of local recurrence but not the risk of disease recurrence or death after 5 yr. (C) 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.