1. Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
2. Institute of Digestive and Liver Diseases, St. Luke's Medical Center, Quezon City, Philippines
3. Department of Diagnostic Pathology, Kobe University Graduate School of Medicine, Kobe, Japan
4. Division of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan