Figure 2. Preoperative CT and intraoperative findings of patient 6. A) Preoperative CT scan image showing a large tumor located between the IVC (asterisk) and the psoas muscle. The IVC was compressed medially. B) The tumor was identified after entering the retroperitoneal space. It was located medially to the psoas muscle. The IVC was compressed medially to the tumor. C) Laparoscopic view during dissection. The IVC had been released from the media side of the tumor. D) Laparoscopic view after resecting the tumor. CT indicates computed tomography; A = aorta; IVC = inferior vena cava; M = mass; P = psoas muscle.