1. Department of Clinical Oncology, Aichi Cancer Center Hospital, Nagoya, Japan;
2. Department of Clinical Oncology, St. Marianna University School of Medicine, Kanagawa, Japan;
3. JCOG Data Center, Multi-institutional Clinical Trial Support Center, National Cancer Center, Tokyo, Japan;
4. Gastrointestinal Oncology Division, National Cancer Center Hospital, Tokyo, Japan;
5. Department of Gastroenterology and Gastrointestinal Oncology, National Cancer Center Hospital East, Kashiwa, Japan;
6. Division of Gastrointestinal Oncology, Shizuoka Cancer Center, Shizuoka, Japan;
7. Department of Gastroenterology, Kitasato University School of Medicine, Sagamihara, Japan;
8. Department of Gastroenterology, Yamagata Prefectural Central Hospital, Yamagata, Japan;
9. Department of Gastroenterology, Saitama Cancer Center Hospital, Saitama, Japan;
10. Cancer Chemotherapy Center, Osaka Medical College, Takatsuki, Japan;
11. Department of Gastrointestinal Medical Oncology, National Hospital Organization Shikoku Cancer Center, Matsuyama, Japan;
12. Division of Diabetes, Digestive and Kidney Diseases, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan;
13. Division of Medical Oncology, Kochi Health Sciences Center, Kochi, Japan