1 Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
2 Department of Visceral Surgery, University Hospital Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
3 Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; National Center for Global Health and Medicine, Tokyo, Japan. Electronic address: [email protected].