1. Medical HQsEisai Co., Ltd. Tokyo Japan
2. Division of GastroenterologyDepartment of Internal MedicineHiroshima Red Cross Hospital & Atomic‐bomb Survivors Hospital Hiroshima Japan
3. Department of Health SciencesFaculty of Human Culture and SciencePrefectural University of Hiroshima Hiroshima Japan
4. Endoscopy DivisionNational Cancer Center Hospital Tokyo Japan
5. Division of GastroenterologyDepartment of Internal MedicineSchool of MedicineIwate Medical University Morioka Japan
6. Department of PathologyOkayama University Graduate School of MedicineDentistry and Pharmaceutical Sciences Okayama Japan
7. Department of Gastroenterology and HematologyGraduate School of Medicine and Pharmaceutical SciencesUniversity of Toyama Toyama Japan