Oncologic Outcome of the Extent of Pelvic Lymph Node Dissection During Radical Prostatectomy: A Systematic Review, Meta-analysis, and Network Analysis

Context Some authors propose extended pelvic lymph node dissection (ePLND) to enhance diagnostic and therapeutic outcomes in patients with localized prostate cancer. However, recent evidence found no difference in biochemical recurrence (BCR). Objective To stratify and analyze available evidence on ePLND and its impact on BCR in patients with localized prostate cancer. Evidence acquisition We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify studies up to November 2023. We identified original articles that presented statistical comparisons through Cox regressions reported as hazard ratio (HR) or survival curve data reported as Kaplan-Meier curve differences in BCR in patients undergoing radical prostatectomy and stratified by the extent of lymph node dissection for localized prostate cancer. Evidence synthesis We identified 12 studies, with two being randomized controlled trials (RCTs). The RCTs showed no benefit of ePLND with an HR of 1.03 ([0.92, 1.14], p = 0.61). A combined analysis with the ten retrospective studies revealed a notable reduction in BCR with an HR of 0.68 ([0.52, 0.88], p = 0.003). A subgroup analysis based on the extent of dissection demonstrated that studies focusing on the more conservative extended template of dissection did not show significant BCR benefit (HR 0.97 [0.72, 1.32], p = 0.86). In contrast, dissections that expanded the anatomical extent showed decreased BCR (HR 0.56 [0.41, 0.75], p < 0.0001). A Bayesian network analysis highlights significant differences in BCR reduction between different dissection approaches, indicating the potential benefits of specific dissection templates. Conclusions Available literature on the extent of pelvic lymph node dissection needs to be improved in quality and varying definitions of the ePLND template. Dissection of the common iliac nodes may be beneficial. Patient summary There is a potential benefit in removing more lymph nodes during radical prostatectomy. However, more research is needed to determine whether this strategy benefits certain patient groups.