1. Departments of Gastroenterology, Aichi Cancer Center Hospital, Japan
2. Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Japan
3. Department of Hepatobiliary and Pancreatic Oncology, National Cancer Center Hospital, Japan
4. Departments of Endoscopy, Aichi Cancer Center Hospital, Japan
5. Departments of Pathology and Molecular Diagnosis, Aichi Cancer Center Hospital, Japan