[1] Department of Gastroenterology,Graduate School of Medicine,the University of Tokyo
[2] Department of Biostatistics,School of Public Health,the University of Tokyo
[3] Center for Epidemiology and Preventive Medicine,Graduate School of Medicine,the University of Tokyo
[4] Department of Endoscopy and Endoscopic Surgery,Graduate School of Medicine,the University of Tokyo
[5] Department of Pathology,Graduate School of Medicine, the University of Tokyo