Surgical Technique
A transperitoneal approach was applied to all patients. LPN was carried out as we described previously [10]. Briefly, following general anesthesia, the left or right lateral decubitus position was performed according to the side of the tumor. Pneumoperitoneum was created with an intra-abdominal pressure of 12-15 mmHg by inserting a Veress needle 1-2 cm superior to the umbilical level from the lateral of the rectus muscle. The optic port was placed at this point where the pneumoperitoneum was created. A total of 4 ports were placed for LPN, one for the camera, one for the right (12mm), and one for left (5mm) hand due to dissection and one for the retraction (5mm) port. If necessary, one more port (5mm) was placed for retraction or traction.
RPN performed by using a four-arm da Vinci XI robotic system (Intuitive Surgical, CA, USA). First, an 8 mm camera port was placed lateral to the rectus muscle. Three robotic working ports (8 mm) and an assistant port were then placed. The robotic system was docked from the back of the patient, and the robotic arms were docking to the ports on the front of the patient. The assistant was involved in the replacement of robotic instruments, the use of aspirators, and the delivery of suture material in the anterior-lateral part of the patient.
The colon deviated medially from the Toldt line. Following the dissection of the hepatorenal or splenorenal ligament, ureter, and gonadal vein identified on the psoas, renal hilum was revealed by followed cranial dissection. The renal artery, vein, and hilum dissected separately. Perinephric adipose tissue was released from the capsule except the adipose tissue covering the tumor. Then the tumor was resected with a cold scissor leaving an approximately 5 mm safety margin after clamping the renal artery. The collector system and vascular structures in the tumor bed were sutured with 3/0 V-Lock with fixed a Hem-o-Lok clip at the end. Than renorrhaphy was completed using 2/0 Vicryl and 2/0 Monocryl suture material fixed with Hem-o-Lok clip to bring the renal parenchyma closer. The bulldog clamps were opened and warm ischemia was terminated. This procedure was applied similarly to both LPN and RPN.