Neoadjuvant immune checkpoint blockade represents a novel approach for potentially decreasing the risk of recurrence in patients with nonmetastatic renal cell carcinoma (RCC). In this early phase clincal tiral, we evaluated the safety and tolerability of neoadjuvant treatment with the programmed cell death protein 1 (PD-1) inhibitor nivolumab in patients with nonmetastatic high-risk RCC.