1. Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan
2. Department of Gastroenterology, St. Mary's Hospital, Kurume, Fukuoka 830‑8543, Japan
3. Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan