1. Department of Surgery College of Medicine, Seoul National University Seoul South Korea
2. Department of Surgery Samsung Medical Center, Sungkyunkwan University School of Medicine Seoul South Korea
3. Department of Hepatobiliary and Pancreatic Surgery Yonsei University College of Medicine Seoul South Korea
4. Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery Ulsan College of Medicine, Asan Medical Center Seoul South Korea
5. Center for Liver and Pancreatobiliary Cancer National Cancer Center Goyang South Korea
6. Department of Surgery Seoul National University Bundang Hospital Sungnam South Korea
7. Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery Keimyung University Dongsan Hospital Daegu South Korea
8. Department of Surgery Seoul Metropolitan Government Seoul National University Boramae Medical Center Seoul South Korea
9. Department of Mathematics and Statistics Sejong University College of Natural Sciences Seoul South Korea
10. Department of Statistics and Interdisciplinary Program in Bioinformatics Seoul National University Seoul South Korea
11. Department of Surgery Nagoya University Graduate School of Medicine Nagoya Japan
12. Department of Gastroenterological Surgery Aichi Cancer Center Hospital Nagoya Japan
13. Second Department of Surgery Wakayama Medical University Wakayama Japan
14. Department of Gastrointestinal and Pediatric Surgery Tokyo Medical University Tokyo Japan
15. Division of Hepato‐Biliary‐Pancreatic Surgery Shizuoka Cancer Center, Japan Shizuoka Japan
16. Division of Hepato‐Biliary‐Pancreatic Surgery, Department of Surgery Kobe University Graduate School of Medicine Kobe Japan
17. Department of General Surgery Graduate School of Medicine, Chiba University Chiba Japan
18. Department of Surgery Tohoku University Graduate School of Medicine Sendai Japan
19. Department of Gastroenterological Surgery Yokohama City University Graduate School of Medicine Yokohama Japan
20. Department of Surgery Keio University School of Medicine Tokyo Japan