1. Department of Hepato-Biliary-Pancreatic Surgery; Osaka City University Graduate School of Medicine; 1-4-3 Asahimachi, Abeno-ku Osaka 545-8585 Japan
2. Department of Human Pathology; Kanazawa University Graduate School of Medicine; Kanazawa Japan
3. Department of Gastroenterological Surgery and Oncology; Kitano Hospital; Tazuke Kofukai Medical Institute; Osaka Japan
4. Department of Surgery; Tane General Hospital; Osaka Japan
5. Department of Gastroenterology; Juntendo University; Tokyo Japan
6. Department of Surgery; Osaka Medical Center for Cancer and Cardiovascular Diseases; Osaka Japan
7. Department of Surgery; Higashisumiyoshi-Morimoto Hospital; Osaka Japan
8. Department of Surgery; National Hospital Organization; Osaka National Hospital; Osaka Japan
9. Department of Hepato-Biliary-Pancreatic Surgery; Osaka Red Cross Hospital; Osaka Japan
10. Department of Hepatology; Osaka City University Graduate School of Medicine; Osaka Japan
11. Department of Surgery; Nissey Hospital; Osaka Japan
12. Department of Digestive Disease and Oncology; National Hospital Organization; Kagoshima Medical Center; Kagoshima Japan
13. Artificial Organ & Transplantation Division; Department of Surgery; University of Tokyo; Tokyo Japan
14. Department of Surgery; Ishikiriseiki Hospital; Osaka Japan
15. Department of Surgery; Kansai Medical University; Osaka Japan
16. Department of Diagnostic Pathology; Osaka City University Graduate School of Medicine; Osaka Japan
17. Department of Preventive Medicine and Environmental Health; Osaka City University Graduate School of Medicine; Osaka Japan