1 Department of Gastroenterological Surgery, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba, 270-2232, Japan.
2 Division of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Tokyo, Japan.
3 Department of Gastroenterological Surgery, New Tokyo Hospital, 1271 Wanagaya, Matsudo, Chiba, 270-2232, Japan. ghon67@outlook.jp.
4 Division of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo-ku, Tokyo, Japan. ghon67@outlook.jp.