1. Department of General Surgical Science, Gunma University Graduate School, Japan
2. Department of Molecular Pharmacology and Oncology, Gunma University Graduate School, Japan
3. Department of Diagnostic and Interventional Radiology, Gunma University Graduate School, Japan
4. Department of Pathology, Gunma University Graduate School, Japan
5. Department of Radiation Oncology, Faculty of Medicine, University of Tsukuba, Japan