1. Hokkaido University Faculty of Medicine and Graduate School of Medicine Department of Radiation Oncology, , North 15 West 7, Kita-ku, Sapporo 060-8638, Japan
2. Hokkaido University Hospital Department of Medical Physics, , North 14 West 5, Kita-ku, Sapporo 060-8648, Japan
3. Hokkaido University Faculty of Engineering Division of Applied Quantum Science and Engineering, , North 13 West 8, Kita-ku, Sapporo 060-8628, Japan
4. Hokkaido University Hospital Department of Diagnostic and Interventional Radiology, , North 14 West 5, Kita-ku, Sapporo 060-8648, Japan
5. Hokkaido University Faculty of Medicine Department of Gastroenterology and Hepatology, , North 15 West 7, Kita-ku, Sapporo 060-8638, Japan
6. Hokkaido University Faculty of Medicine Department of Gastroenterological Surgery, , North 15 West 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan
7. Hokkaido University Hospital Department of Radiation Oncology, , North 14 West 5, Kita-ku, Sapporo 060-8648, Japan