^○Takeshi Sudo, Naoto Hadano, Kohei Ishiyama, Takashi Onoe, Hirotaka Tashiro (Department of Surgery, Kure Medical Center and Chugoku Cancer Center)

^○Yusuke Takahashi, Hitoshi Seki (Department of hepatobiliary pancreatic Surgery, Nagano Municipal Hospital, Nagano, Japan)

^○Shinichiro Kameyama, Tomonari Ishimine, Haruka Motonari (Department of Surgery, Center for Gastroenterology, Urasoe General Hospital)

^○Katsuya Okada, Masayasu Aikawa, Yukihiro Watanabe, Kenichiro Takase, Kojun Okamoto, Isamu Koyama (Department of Digestive Surgery, Saitama Medical University International Medical Center, Saitama, Japan)

^○Kazuaki Hazama, Kazuhiro Iwai, Junkichi Koinuma, Mizuna Takahashi, Hatuki Usui, Sho Sekiya, Mikio Watanabe (Department of Surgery, Oji General Hospital, Tomakomai, Japan)

^○Takaaki Ito, Teiichi Sugiura, Yukiyasu Okamura, Yusuke Yamamoto, Ryo Ashida, Katsuhiko Uesaka (Division of Hepato-Biliary-Pancreatic Surgery, Shizuoka Cancer Center Hospital)