1. Department of Surgery, Nagato Memorial Hospital, Saiki-shi, Oita, Japan
2. Department of Oncological Science (Surgery2), Oita University Faculty of Medicine, Yufu-shi Oita, Japan
3. Department of Gastrointestinal Surgery, Oita University Faculty of Medicine, Yufu-shi Oita, Japan
4. Department of Oncological Science (Urology), Oita University Faculty of Medicine, Yufu-shi Oita, Japan