Lymph node dissection could bring survival benefits to patients diagnosed with clinically node-negative upper urinary tract urothelial cancer: a population-based, propensity score-matched study

ObjectivesTo evaluate the survival benefits that lymph node dissection (LND) brought to clinically node-negative upper tract urothelial carcinoma (UTUC) patients.MethodsNon-metastatic node-negative UTUC patients were identified from the Surveillance, Epidemiology and End Results database. N0 patients were naturally divided as cN0-pNx group (clinically diagnosed as N0 without LND performed) and cNx-pN0 group (pathologically diagnosed as node-negative no matter what clinical node status they have).ResultsOf the 2731 patients included, 2240 and 491 cases were cN0-pNx and cNx-pN0, respectively. The overall survival (OS) of cNx-pN0 patients was significantly better than that of cNx-pN0 patients (p=0.022). After propensity score matching, the survival of cNx-pN0 patients was still significantly better than cN0-pNx group. Besides, multivariate analyses showed cNx-pN0 (received LND) was an independent favorable prognostic factor for OS and CSS compared with cN0-pNx (no LND). Survival advantages of pN0 group were more significant in T2 patients and patients with tumor size5cm. Even in N0 patients who received adjuvant treatment, LND still brought obvious survival improvement (HRos=0.565, p=0.013; HRcss=0.607, p=0.046).ConclusionLND could improve survival outcomes in patients with clinically node-negative UTUC, especially for those with muscle-invasive diseases (T2-4 stages) or smaller tumor size (5cm). Adjuvant treatment after nephroureterectomy is incapable of replacing the therapeutic role of LND.