1. Department of Hepato‐Biliary‐Pancreatic Surgery Uji Tokusyukai Medical Center Kyoto Japan
2. Department of Surgery Nara Medical University Kashihara Japan
3. Department of Surgery, Hirakata Hospital Kansai Medical University Osaka Japan
4. Department of Hepato‐Biliary‐Pancreatic Surgery Osaka City University Graduate School of Medicine Osaka Japan
5. Department of General and Gastroenterological Surgery Osaka Medical College Osaka Japan
6. Department of Gastroenterological Surgery, Graduate School of Medicine Osaka University Osaka Japan
7. Second Department of Surgery Wakayama Medical University Wakayama Japan
8. Department of Surgery, Faculty of Medicine Kindai University Osaka Japan
9. Division of Digestive Surgery, Department of Surgery Kyoto Prefectural University of Medicine Kyoto Japan
10. Division of Gastrointestinal, Breast, and General Surgery, Department of Surgery Shiga University of Medical Science Otsu Japan