1. Multidisciplinary Treatment Cancer Center, Kurume University Hospital, Kurume, Fukuoka 830‑0011, Japan
2. Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan
3. Biostatistics Center, Kurume University, Kurume, Fukuoka 830‑0011, Japan
4. Department of Surgery, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan