Lymph node dissection during radical nephrectomy: A Canadian multi-institutional analysis

Abstract

ObjectivesTo determine the association between lymph node dissection (LND) at the time of radical nephrectomy and survival in a large, multi-institutional cohort using a propensity score matching design. Subjects and MethodsThe Canadian Kidney Cancer information system was used to identify patients undergoing radical nephrectomy for nonmetastatic renal cell carcinoma. Associations between LND with overall survival , recurrence free survival and cancer specific survival were determined using various propensity score techniques in the overall cohort and in patients with varying probabilities of pN1. Cox models were used to determine association of lymph node removed with outcomes. ResultsOf the 2,699 eligible patients, 812 (30%) underwent LND. Of the LND patients, 88 (10.8%) had nodal metastases. There was no association between LND and improved overall survival, recurrence free survival or cancer specific survival using various propensity score techniques (stratification by propensity score quintile, matched pairs, inverse treatment probability weighting and adjusted for propensity score quintile). There was no association between LND and a therapeutic benefit in patients with increased threshold probabilities of nodal metastases. Increased number of lymph nodes removed was not associated with improved survival outcomes. ConclusionsLND at the time of radical nephrectomy for renal cell carcinoma is not associated with improved outcomes. There was no benefit in patients at high risk for nodal metastases, and the number of nodes removed did not correlate with survival. Further studies are needed to determine which high risk patients may benefit from LND.