1. Department of Gastrointestinal Oncology, Hyogo Cancer Center, Akashi, Hyogo, Japan
2. Department of Gastroenterology, Ishikawa Prefectural Central Hospital, Kanazawa, Ishikawa, Japan
3. Department of Gastroenterology and Endoscopy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
4. Department of Therapeutic Oncology, Kyoto University Graduate School of Medicine, Kyoto, Kyoto, Japan
5. Department of Gastrointestinal Oncology, Osaka International Cancer Institute, Osaka, Osaka, Japan
6. Division of Endoscopy, Shizuoka Cancer Center, Suntogun, Shizuoka, Japan
7. Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Okayama, Japan
8. Department of Endoscopy, National Hospital Organization Shikoku Cancer Center, Matsuyama, Ehime, Japan
9. Department of Endoscopy, Fukuoka University Chikushi Hospital, Chikushino, Fukuoka, Japan
10. Endoscopy Division, National Cancer Center Hospital, Chuo, Tokyo, Japan
11. Department of Gastroenterology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
12. Endoscopy Division, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan
13. Department of Gastroenterology, NTT Medical Center Tokyo, Shinagawa, Tokyo, Japan
14. Department of Biostatistics, Hiroshima University Hospital, Hiroshima University, Hiroshima, Japan
15. Department of Molecular-Targeting Cancer Prevention, Kyoto Prefectural University of Medicine, Kyoto, Japan