Benefit from cytoreductive nephrectomy and the prognostic role of neutrophil-to-lymphocyte ratio in patients with metastatic renal cell carcinoma

Background: The role of cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC) in the era of targeted therapies is currently undefined. In recent years, neutrophil-to-lymphocyte ratio (NLR) has emerged as a prognostic marker in several cancers, including mRCC. In this multicentre retrospective study, we aim to assess the impact of CN in mRCC and the value of NLR in risk stratification and patient selection. Methods: Retrospective data from patients with de novo mRCC from four large Australian hospitals were collected. Survival analyses were performed using the Kaplan–Meier method and compared using the log-rank test. Multivariate analyses were performed using the Cox proportional hazards method. Results: Our study identified 91 de novo mRCC patients. Patients who underwent CN (n = 46, 51%) were more likely to be younger (59.0 years vs 64.6 years, P = 0.019) and to have received systemic therapy (91% vs 76%, P = 0.043). Median overall survival (mOS) was significantly improved in patients who underwent CN (23.0 months vs 10.9 months, hazard ratios (HR) 0.33, 95% confidence interval (CI) 0.20–0.55, P < 0.0001). Patients with NLR ≥ 5 also had inferior mOS (6.2 months vs 16.7 months, HR 1.94, 95% CI 1.14–3.29, P = 0.014). CN was associated with substantially improved survival in patients with both NLR < 5 (mOS 31.1 months vs 7.0 months, HR 0.41, 95% CI, 0.18–0.64, P = 0.0009) and NLR ≥ 5 (mOS 10.9 months vs 2.3 months, HR 0.33, 95% CI, 0.11–0.69, P = 0.009). Significant survival benefits associated with CN were maintained in multivariate analyses (HR 0.39, 95% CI 0.22–0.70, P = 0.0014). Conclusions: CN is associated with significantly improved overall survival in de novo mRCC. The incremental survival benefit associated with CN was seen irrespective of NLR.