Robot‐assisted partial nephrectomy via retroperitoneal approach in a patient with horseshoe kidney

Horseshoe kidney is a renal fusion anomaly often associated with ectopia, malformation, and vascular changes. Robot‐assisted partial nephrectomy is selected for patients with T1a renal cell carcinoma; however, there are few reports of renal cell carcinoma in horseshoe kidney. We present a case of robot‐assisted partial nephrectomy via a retroperitoneal approach in a patient with horseshoe kidney with a brief literature review. Case presentation An 84‐year‐old woman presented with a 2‐cm mass in horseshoe kidney. She underwent robot‐assisted laparoscopic partial nephrectomy via a retroperitoneal approach. Conclusion The use of robot‐assisted laparoscopic partial nephrectomy in patients with horseshoe kidney is very rare, and only four cases have been reported. Because of the unique anatomical structure, surgeons need to consider surgical strategy more carefully, considering tumor location, vascular anatomy, and past history of abdominal surgery.