1. Department of Digestive Surgery Nihon University School of Medicine Tokyo Japan
2. Department of Biostatistics University of Tokyo Tokyo Japan
3. Department of Hepato‐Biliary‐Pancreatic Surgery Osaka Metropolitan University Graduate School of Medicine Osaka Japan
4. Department of Surgery National Center for Global Health and Medicine Tokyo Japan
5. Department of Gastroenterology and Hepatology Musashino Red Cross Hospital Musashino Japan
6. Department of Radiology Kobe University Graduate School of Medicine Kobe Japan
7. Department of Gastroenterology Juntendo University School of Medicine Tokyo Japan
8. Department of Gastroenterology and Hepatology Kinki University School of Medicine Kobe Japan
9. Department of Pathology Keio University School of Medicine Tokyo Japan
10. Laboratory Services Center St. Mary’s Hospital Kurume Japan
11. Department of Surgery Division of Hepato‐Biliary‐Pancreatic Surgery Kobe University Graduate School of Medicine Kobe Japan
12. Department of Internal Medicine Division of Gastroenterology and Hepatology Hyogo College of Medicine Nishinomiya Japan
13. Department of Surgery Nagasaki University Graduate School of Biomedical Sciences Nagasaki Japan
14. Department of Surgery Division of Gastroenterological Hapato‐Biliary‐Pancreatic, Transplantation, and Pediatric Surgery Shinshu University School of Medicine Matsumoto Japan
15. Department of Hepato‐Biliary‐Pancreatic Surgery Japanese Red Cross Medical Center Tokyo Japan