Robot-assisted laparoscopic surgery for rectal cancer in a patient with a horseshoe kidney: A case report.

A 52-year-old, Japanese man presented to the hospital with a complaint of anal bleeding, and detailed examination resulted in a diagnosis of locally advanced rectal cancer. The patient underwent total neoadjuvant therapy followed by short-course radiation therapy and consolidation chemotherapy, which provided a partial response. After preoperative contrast-enhanced computed tomography showed a horseshoe kidney, robot-assisted, precise, laparoscopic, low anterior resection with D3 dissection and ileostomy construction was performed. The horseshoe renal isthmus was elevated surrounding the inferior mesenteric artery, and the left ureter and seminal vessels ran in front of the kidney. The hypogastric nerve traveled ventral to the horseshoe kidney. With robotic surgery, it was possible to perform more precise surgery while recognizing vascular and nerve anatomy in a rectal cancer patient with a horseshoe kidney due to good three-dimensional visibility and articulated forceps manipulation.