The Role of Cytoreductive Nephrectomy in Metastatic Renal Cell Carcinoma: A Real-World Multi-Institutional Analysis

Purpose: The role of cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC) was challenged by the results of the CARMENA trial. Here we evaluate the role of CN in mRCC patients, including those receiving modern therapies. Materials and Methods: We included patients with synchronous mRCC between 2011-2020 from the de-identified nationwide Flatiron Health database. We evaluated 3 groups: systemic therapy alone, CN followed by systemic therapy (up-front CN [uCN]) and systemic therapy followed by CN (deferred CN [dCN]). The primary outcome was median overall survival (mOS) in patients receiving systemic therapy alone vs uCN. Secondary outcome was overall survival in patients receiving uCN vs dCN. First-treatment, landmark and time-varying covariate analyses were conducted to overcome immortal time bias. Weighted Kaplan-Meier curves, log-rank tests and Cox proportional hazards regressions were used to assess the effect of therapy on survival. Results: Of 1,910 patients with mRCC, 972 (57%) received systemic therapy, 605 (32%) received uCN, 142 (8%) dCN and 191 (10%) CN alone; 433 (23%) patients received immunotherapy-based therapy. The adjusted mOS was significantly improved in first-treatment, landmark and time-varying covariate analysis (mOS 26.6 vs 14.6 months, 36.3 vs 21.1 months and 26.1 vs 12.2 months, respectively) in patients undergoing CN. Among patients receiving CN and systemic therapy, the timing of systemic therapy relative to CN was not significantly related to overall survival (HR=1.0, 95% CI 0.76-1.32, p=0.99). Conclusions: Our findings support an oncologic role for CN in select mRCC patients. In patients receiving both CN and systemic therapy, the survival benefit compared to systemic alone was similar for up-front and deferred CN.