Influence of lymph node dissection in patients undergoing radical nephrectomy for non-metastatic renal cell carcinoma: A systematic review and meta-analysis

OBJECTIVE: Whether lymph node dissection (LND) should be performed concomitantly with radical nephrectomy (RN) for non-metastatic renal carcinoma has still been controversial recently. We conducted a meta-analysis assessing oncologic outcomes of radical nephrectomy with lymph node dissection (LND) and without lymph node dissection (non-LND) in non-metastatic renal cell carcinoma (NMRCC). PATIENTS AND METHODS: A systematic review was performed until April 2018 using a comprehensive search in PubMed, EMBASE, and Cochrane Library databases to identify eligible comparative studies. A formal meta-analysis was performed for studies comparing radical nephrectomy with LND and radical nephrectomy with non-LND for cT₁-T₄N_xM₀ tumors. Furthermore, a subgroup analysis for locally advanced renal cell carcinoma (cT₃-T₄N_xM₀) was conducted. RESULTS: Thirteen studies on patients with LND and non-LND were identified and included in the analysis. LND group did not have a significantly better survival than non-LND group for cT₁-T₄N_xM₀ tumors (HR 0.93, 95% CI 0.78-1.11, p=0.45), However, in the subgroup of locally advanced renal cell carcinoma (cT₃-T₄N_xM₀), it showed a significantly better OS rate in patients who had undergone LND compared to those without LND (HR 0.73, 95% CI 0.60-0.90; p=0.003). CONCLUSIONS: LND offers better cancer control and better long-term survival in locally advanced renal cell carcinomas (cT₃-T₄N_xM₀). This conclusion should be confirmed by a prospective randomized clinical trial.