1. Department of Hepatobiliary and Pancreatic Oncology, Osaka International Cancer Institute, Osaka 541-8567, Japan
2. Department of Radiation Oncology, Osaka International Cancer Institute, Osaka 541-8567, Japan
3. Department of Diagnostic and Interventional Radiology, Osaka International Cancer Institute, Osaka 541-8567, Japan
4. Department of Gastroenterological Surgery, Osaka International Cancer Institute, Osaka 541-8567, Japan