1. Department of Hepatobiliary and Pancreatic Oncology; Osaka Medical Center for Cancer and Cardiovascular Diseases; 1-3-3 Nakamichi Higashinari-ku Osaka Osaka 537-8511 Japan
2. Kyoto University Hospital; Outpatient Oncology Unit; Kyoto University; Kyoto Japan
3. Department of Surgery; Division of Hepato-Biliary-Pancreatic Surgery; Kobe University; Graduate School of Medicine; Kobe Japan
4. Hepato-Biliary-Pancreatic Surgery; Osaka City General Hospital; Osaka Japan
5. Department of Surgery; Kansai Medical University; Osaka Japan
6. Department of Gastroenterological Surgery and Oncology; Kitano Hospital; The Tazuke Kofukai Medical Research Institute; Osaka Japan
7. Department of Abdominal Surgery; Tenri Hospital; Nara Japan
8. Department of Surgery; Osaka University; Graduate School of Medicine; Osaka Japan
9. Department of Surgery; National Hospital Organization Kyoto Medical Center; Kyoto Japan
10. Department of Surgery; Hyogo College of Medicine; Hyogo Japan
11. Department of Surgery; Kansai Electric Power Hospital; Osaka Japan
12. Department of Surgery; Kyoto Prefectural University of Medicine; Kyoto Japan
13. Department of Hepatobiliary Pancreatic Surgery; Osaka City University Graduate School of Medicine; Osaka Japan
14. Department of Surgery; Osaka National Hospital; Osaka Japan
15. Department of Surgery; Asahi University Murakami Memorial Hospital; Gifu Japan
16. Department of Surgery; Bell Land General Hospital; Osaka Japan
17. Hepato-Biliary-Pancreatic Surgery; Department of Surgery; Kansai Rosai Hospital; Hyogo Japan
18. Department of Surgery; Otsu Red Cross Hospital; Otsu Shiga Japan
19. Department of Hepatobiliary and Pancreatic Oncology; Osaka Medical Center for Cancer and Cardiovascular Diseases; Osaka Japan