Shifting role of cytoreductive nephrectomy according to type of systemic therapy: A nationwide cohort study

Purpose The best protocol of cytoreductive nephrectomy (CN) and systemic therapy (ST) in the treatment of metastatic renal cell carcinoma (mRCC) remains unclear. We sought to evaluate overall survival (OS) in patients with mRCC treated with ST with or without CN. Methods We collected data from the National Health Insurance Service database. We excluded 2 years of washout period, 2 years of follow-up period, other cancer diagnoses within 2 years, and ≥4 months interval between ST and CN. The patients were divided into two groups according to whether CN was performed. Kaplan–Meier, propensity score matching, Cox regression model, and incremental survival analyses were conducted. Additionally, we performed subgroup analysis according to whether cytokine therapy or targeted therapy was used as first-line ST. Results Of 6478 patients, 1707 (26.4%) underwent CN. The CN group showed significantly better OS than the no CN group (p < 0.001). In the cytokine therapy subgroup, patients who underwent CN had significantly higher OS than those who did not (p < 0.001). In the targeted therapy subgroup, no significant difference was found (p = 0.867). In multivariate analysis, CN was associated with better OS in the total cohort (hazard ratio 0.819, p < 0.001). The incremental OS benefit of CN ranged from +0.98 in patients who survived for <24 months to +2.13 in those who survived during all periods. Conclusion About a quarter patients with mRCC from a nationwide database were treated with CN and ST. CN was beneficial in specific patients with mRCC. Patient selection is crucial for obtaining the benefits of CN.