1. Department of Gastroenterology Medicine Center, Shonan Kamakura General Hospital Kamakura Kanagawa Japan
2. Division of Medical Oncology/Hematology, Department of Medicine Kobe University Graduate School of Medicine Kobe Hyogo Japan
3. Department of Gastroenterology Saitama Medical University International Medical Center Saitama Japan
4. Department of Gastroenterology, Internal Medicine Kitasato University School of Medicine Sagamihara Kanagawa Japan