1. Department of Surgery, Seoul National University Hospital, Seoul, Korea
2. Department of Surgery, Gachon University Gil Medical Center, Incheon, Korea
3. Department of Surgery and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea
4. Department of Surgery, Chung-Ang University Hospital, Seoul, Korea
5. Department of Surgery, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
6. Department of Surgery, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Korea
7. Department of Surgery, Pusan National University Yangsan Hospital, Yangsan, Korea
8. Department of Surgery, Dankook University College of Medicine, Cheonan, Korea
9. Department of Surgery, CHA Bundang Medical Center, CHA University, Seongnam, Korea
10. Department of Surgery, Keimyung University School of Medicine, Daegu, Korea
11. Department of Surgery, Yonsei University Wonju College of Medicine, Wonju, Korea
12. Department of Surgery, The Catholic University of Korea Yeouido St. Mary’s Hospital, Seoul, Korea
13. Department of Surgery, Pusan National University College of Medicine, Busan, Korea
14. Department of Surgery, Kyung Hee University Hospital at Gangdong, Seoul, Korea
15. Department of Surgery, Gyeongsang National University College of Medicine, Jinju, Korea
16. Department of Surgery, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea
17. Department of Medical Research Collaborating Center, Seoul National University Hospital, Seoul, Korea