1. Department of Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
2. Department of Surgery, Ewha Womans University Mokdong Hospital, Seoul 07985, Republic of Korea
3. Division of Hepatobiliary-Pancreatic Surgery, Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
4. Department of Hepatobiliary and Pancreatic Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
5. Department of Surgery, Jeonbuk National University Hospital, Jeonbuk National University Medical School, Jeonju 54896, Republic of Korea
6. Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
7. Department of Surgery, College of Medicine, Incheon St. Mary’s Hospital, Catholic University of Korea, Seoul 06591, Republic of Korea
8. Division of Hepato-Pancreato-Biliary Surgery, Department of Surgery, Chonnam National University Medical School, Chonnam National University Hospital, Gwangju 61469, Republic of Korea