Yosuke Kataoka1, Yosuke Tsuji1, Kingo Hirasawa2, Kengo Takimoto3,4, Tomonori Wada5, Satoshi Mochizuki6, Ken Ohata7, Yoshiki Sakaguchi1, Keiko Niimi1,8, Satoshi Ono9, Shinya Kodashima10, Nobutake Yamamichi1, Mitsuhiro Fujishiro1,11, Kazuhiko Koike1. 1. Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 2. Division of Endoscopy, Yokohama City University Medical Center, Kanagawa, Japan. 3. Department of Gastroenterology, Takeda General Hospital, Kyoto, Japan. 4. Department of Gastroenterology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan. 5. Department of Gastroenterology, Sanraku Hospital, Tokyo, Japan. 6. Shinagawa Gut Clinic, Tokyo, Japan. 7. Department of Gastroenterology, NTT Medical Center Tokyo, Tokyo, Japan. 8. Center for Epidemiology and Preventive Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. 9. Department of Gastroenterology, Chiba-Nishi General Hospital, Matsudo, Japan. 10. Department of Gastroenterology, Teikyo University School of Medicine, Tokyo, Japan. 11. Department of Endoscopy and Endoscopic Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.