Synchronous Bilateral Large Renal Cell Carcinoma Treated With Presurgical Pembrolizumab and Lenvatinib Enabling Unilateral Partial Nephrectomy and Dialysis Avoidance: A Case Report

Introduction Synchronous bilateral renal cell carcinoma is a rare clinical entity that poses considerable challenges in establishing an optimal treatment strategy. Case Presentation A 56‐year‐old woman had synchronous bilateral renal cell carcinoma, with tumors in the right (61 mm) and left (71 mm) kidneys. Systemic therapy with pembrolizumab and lenvatinib was administered for five months, resulting in tumor reduction to 35 mm (right) and 52 mm (left). This facilitated right partial nephrectomy and then left radical nephrectomy to achieve complete tumor resection with preserved renal function and avoidance of dialysis. Conclusion Pre‐surgical therapy with pembrolizumab and lenvatinib effectively shrank the initially unresectable renal tumors to enable successful partial nephrectomy. This approach may be viable for patients with large bilateral renal masses.