1. Department of Gastroenterology and Hepatology, Gunma University Graduate School of Medicine, 3-39-15 Syowa-machi, Maebashi 371-8511, Gunma, Japan
2. Gunma Health Foundation, Gunma Prefectural Cancer Registry, 16-1 Horinoshita-machi, Maebashi 371-0005, Gunma, Japan
3. Gunma University Center for Food Science and Wellness, 4-2 Aramaki-machi, Maebashi 371-8510, Gunma, Japan