1. Department of Surgery, Japanese Red Cross Asahikawa Hospital, Asahikawa, Japan
2. Department of Gastroenterological Surgery II, Faculty of Medicine, Hokkaido University, Sapporo, Japan
3. Department of Surgical Pathology, Japanese Red Cross Asahikawa Hospital, Asahikawa, Japan
4. Department of Thoracic Surgery, Japanese Red Cross Asahikawa Hospital, Asahikawa, Japan