Lymph node yield and tumor location in patients with upper tract urothelial carcinoma undergoing nephroureterectomy affects survival: A U.S. population-based analysis (2004-2012).

PURPOSE: The purpose of the study was to characterize the contemporary trends in lymphadenectomy for the treatment of upper tract urothelial carcinoma in a population-based cohort and to determine if number of lymph nodes removed and tumor location are predictors of cancer-specific survival in patients undergoing nephroureterectomy.

MATERIALS AND METHODS: Individuals with upper tract urothelial carcinoma undergoing nephroureterectomy in the Surveillance, Epidemiology, and End Results program from 2004 to 2012 were identified. Linear regression was used to assess trends in lymphadenectomy. Patients were stratified based on nodal status, quartiles of nodes removed, and tumor location. Kaplan-Meier analysis, log-rank tests, and Cox proportional hazards models were used to compare cancer-specific survival and overall survival among groups.

RESULTS: In the cohort, 25% (721/2,862) of all patients and 27% (566/2,079) of grade 3/4 patients underwent lymphadenectomy. The percentage of patients undergoing lymphadenectomy increased from 20% (60/295) in 2004 to 33% (106/320) in 2012 (P = 0.02). Patients with the highest quartile of lymph nodes removed had improved the 5-year cancer-specific survival of 78% (95% CI: 69%-85%) compared to the second quartile (60%; 95% CI: 51%-67%; P = 0.003) and the third quartile (60%; 95% CI: 51%-68%; P = 0.002) of nodes removed. This trend held for node-negative and node-positive patients. In multivariable modeling, a lower number of lymph nodes dissected (hazard ratio = 0.94, 95% CI: 0.91-0.98) and ureteral tumors (hazard ratio = 1.29, 95% CI: 1.07-1.56) were predictors of worse cancer-specific survival.

CONCLUSIONS: In patients with upper tract urothelial carcinoma undergoing nephroureterectomy, rates of lymphadenectomy have increased from 2004 to 2012 in the United States. In this contemporary cohort, an increase in the number of nodes removed and renal pelvis tumors are associated with improved cancer-specific survival, which highlights the importance of intentional lymph node dissection with adequate lymph node yield in these patients.