Lymphadenectomy Improves Survival of Patients With Renal Cell Carcinoma and Nodal Metastases

Purpose: In a population based cohort we determined whether an increase in the number of lymph nodes removed is associated with improved disease specific survival of patients with renal cell carcinoma treated with nephrectomy. Materials and Methods: Patients in the Surveillance, Epidemiology and End Results database with renal cell carcinoma and no evidence of distant metastases were identified. Those patients included in the study underwent radical or partial nephrectomy with lymphadenectomy. Cox regression analyses were performed to identify factors associated with disease specific survival including an interaction between lymph node status and the number of lymph nodes removed. Results: Between 1988 and 2006, 9,586 patients with renal cell carcinoma met the study inclusion criteria. Median followup was 3.5 years (range 1.4 to 6.8). Of the patients 2,382 (25%) died of renal cell carcinoma, including 1,646 (20%) with lymph node negative disease and 736 (58%) with lymph node positive disease. There was no effect on disease specific survival with increasing the extent of lymphadenectomy in patients with negative lymph nodes (HR 1.0, 95% CI 0.9-1.1, p = 0.93). However, patients with positive lymph nodes had increased disease specific survival with extent of lymphadenectomy (HR 0.8 per 10 lymph nodes removed, 95% CI 0.7-1.0, p = 0.04). An increase of 10 lymph nodes in a patient with 1 positive lymph node was associated with a 10% absolute increase in disease specific survival at 5 years (p = 0.004). Conclusions: This study shows an association between increased lymph node yield and improved disease specific survival of patients with lymph node positive nonmetastatic renal cell carcinoma who underwent lymphadenectomy. Patients at high risk for nodal disease should be considered for regional or extended lymphadenectomy. Clinical variables to predict risk and validation of dissection templates are important areas for future research.