1. Department of Gastroenterological and Transplant Surgery, Graduate School of Biomedical and Health Sciences Hiroshima University Hiroshima Japan
2. Department of Surgery Hiroshima City Hiroshima Citizens Hospital Hiroshima Japan
3. Department of Gastrointestinal Surgery and Surgical Oncology Ehime University Graduate School of Medicine Toon Japan
4. Department of Surgery National Hospital Organization Higashihiroshima Medical Center Higashihiroshima Japan
5. Department of Surgery Onomichi General Hospital Onomichi Japan
6. Department of Surgery Hiroshima Hiramatsu Hospital Hiroshima Japan
7. Advanced Medical Skills Training Center, Institute of Biomedical and Health Sciences Hiroshima University Hiroshima Japan