1. Department of Gastroenterological Surgery, Kansai Rosai Hospital, Hyogo, Japan
2. Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan
3. Department of Surgery, Kawanishi City Hospital, Kawanishi, Japan
4. Department of Mathematical Health Science, Graduate School of Medicine, Osaka University, Osaka, Japan
5. Department of Surgery, Osaka Police Hospital, Osaka, Japan
6. Department of Surgery, Saiseikai Senri Hospital, Osaka, Japan
7. Department of Gastroenterological Surgery, Osaka Rosai Hospital, Osaka, Japan
8. Department of Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan
9. Department of Surgery, Rinku General Medical Center, Izumisano Municipal Hospital, Osaka, Japan
10. Department of Surgery, Japan Community Health Care Organization Osaka Hospital, Osaka, Japan
11. Department of Surgery, Kinki Central Hospital, Hyogo, Japan
12. Department of Gastroenterological Surgery, Osaka International Cancer Institute, Osaka, Japan