1. Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan
2. Department of Pathology, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan
3. Department of Surgery, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan