1. Department of Gastrointestinal Medical Oncology, National Cancer Center Hospital, Chuo‑ku, Tokyo 104‑0045, Japan
2. Department of Clinical Laboratory, National Cancer Center Hospital, Chuo‑ku, Tokyo 104‑0045, Japan
3. Department of Radiation Oncology, National Cancer Center Hospital, Chuo‑ku, Tokyo 104‑0045, Japan
4. Department of Esophageal Surgery, National Cancer Center Hospital, Chuo‑ku, Tokyo 104‑0045, Japan
5. Multidisciplinary Treatment Cancer Center, Kurume University Hospital, Kurume, Fukuoka 830‑0011, Japan
6. Division of Gastroenterology, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan