1. Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
2. Department of Surgery, Ajou University School of Medicine, Suwon, Republic of Korea
3. Department of Surgery, Dong-A University College of Medicine, Busan, Republic of Korea
4. Department of Surgery, Yeouido St Mary's Hospital, The Catholic University of Korea, College of Medicine, Seoul, Republic of Korea
5. Department of Surgery, Seoul National University College of Medicine, Seoul, Republic of Korea
6. Department of Surgery, Keimyung University School of Medicine, Daegu, Republic of Korea
7. Department of Surgery, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Republic of Korea
8. Department of Surgery, Chonbuk National University Hospital, Jeonju, Republic of Korea
9. Department of Surgery, Seoul St. Mary's Hospital, The Catholic University of Korea, College of Medicine, Seoul, Republic of Korea
10. Department of Surgery, Chungnam National University Hospital, Daejeon, Republic of Korea
11. Department of Surgery, Chonnam National University Medical School, Gwangju, Republic of Korea
12. Department of Surgery, Ewha Womans University Mokdong Hospital, Seoul, Republic of Korea.
13. Department of Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea