1. Department of Medical Oncology, Tonan Hospital, Sapporo, Japan
2. Department of Gastroenterological Surgery, Kumamoto University, Kumamoto, Japan
3. Department of Clinical Oncology, Osaka City General Hospital, Osaka, Japan
4. Cancer Treatment Center, Kochi Medical School Hospital, Nankoku, Japan
5. Department of Surgery and Science, Kyushu University, Fukuoka, Japan
6. Cancer Chemotherapy Center, Osaka Medical College Hospital, Takatsuki, Japan
7. Department of Surgical Oncology, Gifu University, Gifu, Japan
8. Department of Cancer Information Research, National Hospital Organization Kyushu Cancer Center, Fukuoka, Japan
9. Division of Gastrointestinal Surgery, Kobe University Hospital, Kobe, Japan
10. Department of Internal Medicine, Division of Clinical Oncology and Hematology, The Jikei University School of Medicine, Tokyo, Japan