1. Department of Gastroenterology and Hepatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
2. Department of Endoscopy, Nagoya University Hospital, Nagoya, Japan
3. Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan
4. Department of Gastroenterology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan