1) Division of Gastrointestinal Surgery, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, Japan
2) Department of Hepato–Biliary–Pancreatic and Transplant Surgery, Fukushima Medical University, Fukushima, Japan
3) Department of Surgery, National Defense Medical College, Tokorozawa, Japan
4) Department of Surgery, Keio University School of Medicine, Tokyo, Japan
5) Department of Gastrointestinal Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
6) Department of Health Policy and Management, School of Medicine, Keio University, Tokyo, Japan
7) Hamamatsu University School of Medicine, Hamamatsu, Japan
8) Osaka General Medical Center, Osaka, Japan

Yoshihiro Kakeji¹⁾, Shigeru Marubashi²⁾, Hideki Ueno³⁾, Yuko Kitagawa⁴⁾, Yasuyuki Seto⁵⁾, Hiroaki Miyata⁶⁾, Hiroyuki Konno⁷⁾, Mitsukazu Gotoh⁸⁾