1. Department of Gastroenterological Surgery; Kochi Health Sciences Center; Kochi Japan
2. Department of Gastroenterology; Kochi Health Sciences Center; Kochi Japan
3. Department of Diagnostic Pathology; Kochi Health Sciences Center; Kochi Japan
4. Department of Radiology; Kochi Health Sciences Center; Kochi Japan
5. Department of Surgery; Applied Life Sciences Institute of Biomedical and Health Sciences; Hiroshima University; Hiroshima Japan