Benefit of lymph node dissection in cN+ patients in the treatment of upper tract urothelial carcinoma: Analysis of NCDB registry

The benefits of lymph node dissection (LND) in surgically treated upper tract urothelial carcinoma (UTUC) patients who present with clinically positive nodes at diagnosis remain unclear. The aim of this study was to assess survival differences in cN+ patients who underwent radical nephroureterectomy (RNU) with LND vs. without LND.The National Cancer Database was used to identify a total number of 423 cN+ patients from 2004 to 2016 with UTUC that underwent RNU. Of the 423 patients, 310 received LND. Kaplan-Meier (KM) plots were used to estimate survival in cN+ patients who received RNU with LND vs. without. Cox proportional hazards regression tested the impact of LND status on overall survival (OS) after adjusting for all available covariates.Median age of the patient population was 68 years (IQR 61-76), and 56.74% were male. Median follow-up was 1.8 years (IQR 0.9-3.5). For the entire cohort, the 2-year OS rate was 51.8%, and it was 52.1% vs. 51.1% in patients who underwent LND vs. not (log-rank p-value=0.2). On multivariable analysis, performing LND had no statistically significant impact on OS (HR 0.93 95%CI 0.696-1.235, P = 0.9). Repeating the analysis in patients who had exclusively cN1 (HR 0.76 95%CI 0.469-1.223, P = 0.26) or cN2/3 (HR 0.844 95%CI 0.556-1.28, P = 0.43) disease also failed to demonstrate a significant impact of LND on survival.In cN+ patients with UTUC, performing LND in addition to RNU at any clinical stage does not seem to have a significant impact on OS.