1. 1 Department of Surgical Oncology, Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
2. 2 Department of Surgery, Sasebo City General Hospital, Nagasaki, Japan
3. 3 Department of Surgery, National Hospital Organization Nagasaki Medical Center, Nagasaki, Japan
4. 4 Department of Surgery, Isahaya General Hospital, Nagasaki, Japan
5. 5 Department of Surgery, Ureshino Medical Center, Saga, Japan
6. 6 Department of Surgery, Saiseikai Nagasaki Hospital, Nagasaki, Japan