Diagnostic and Prognostic Significance of Radiologic Node-positive Renal Cell Carcinoma in the Absence of Distant Metastases: A Retrospective Analysis of Patients Undergoing Nephrectomy and Lymph Node Dissection

The aim of this study was to evaluate the diagnostic and prognostic value of clinical-positive nodes at preoperative imaging (cN1) in patients with non-metastatic renal cell carcinoma (RCC) treated with lymph node dissection (LND). We retrospectively reviewed data for a cohort of 440 consecutive patients (cN0, 76.8%; cN1, 23.2%) with cTanyNanyM0 RCC who underwent nephrectomy and LND from 1994 to 2013. Metastasis-free survival (MFS) and cancer-specific survival (CSS) were estimated using the Kaplan-Meier method. Multivariate Cox regression analysis was performed to determine significant predictors of MFS and CSS. The mean number of lymph nodes (LNs) examined for all patients was 8.3, and pN1 disease was identified in 31 (7.0%). LN staging by preoperative imaging had a sensitivity of 65%, a specificity of 80%, and an accuracy of 77%. During a median follow-up of 69 months, 5-yr MFS and CSS were 83.6% and 91.3% in patients with cN0 and 49.2% and 70.1% in patients with cN1, demonstrating a trend toward worse prognosis with radiologic lymphadenopathy (all P < 0.001). Furthermore, differences in MFS and CSS between the cN0pN0 and cN1pN0 groups were significant (all P < 0.001). Clinical nodal involvement is an important determinant of adverse prognosis in patients with non-metastatic RCC who undergo LND.