1. Department of Surgery, National Health Insurance Service Ilsan Hospital, Goyang, Korea.
2. Department of Surgery, Dongnam Institute of Radiological and Medical Sciences, Cancer Center, Busan, Korea.
3. Department of Surgery, Gyeongsang National University School of Medicine, Jinju, Korea.
4. Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
5. Department of Surgery, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu, Korea.
6. Department of Surgery, Inje University Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea.
7. Department of Surgery, Korea University College of Medicine, Seoul, Korea.
8. Department of Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
9. Department of Surgery, Ajou University School of Medicine, Suwon, Korea.
10. Department of Surgery, Dankook University Hospital, Cheonan, Korea.
11. Department of Surgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
12. Department of Surgery, Korea Cancer Center Hospital, Seoul, Korea.
13. Department of Surgery, Konyang University Hospital, Daejeon, Korea.
14. Department of Surgery, Kosin University College of Medicine, Busan, Korea.
15. Department of Surgery, G Sam Hospital, Gunpo, Korea.
16. Department of Surgery, Jeju National University Hospital, Jeju, Korea.
17. Department of Surgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
18. Department of Surgery, Kyung Hee University Hospital at Gangdong, Seoul, Korea.
19. Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
20. Department of Surgery, Jeonbuk National University College of Medicine, Jeonju, Korea.
21. Department of Surgery, Daegu Catholic University College of Medicine, Daegu, Korea.
22. Department of Surgery, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
23. Department of Surgery, Hallym University Dongtan Sacred Heart Hospital, Hwaseong, Korea.
24. Department of Surgery, Eulji University Hospital, Daejeon, Korea.
25. Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.