1. Department of Surgery, Seoul National University College of Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul, Republic of Korea
2. Department of Surgery, The Catholic University of Korea St. Vincent's Hospital, Seoul, Republic of Korea
3. Department of Surgery, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
4. Department of Surgery, Asan Medical Center, Seoul, Republic of Korea
5. Department of Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea
6. Department of Surgery, Kyungpook National University School of Medicine, Daegu, Republic of Korea
7. Department of Surgery, SaeGyaeRo Hospital, Busan, Republic of Korea
8. Department of Surgery, Dankook University College of Medicine, Cheonan, Republic of Korea