1. Division of Cancer Immunotherapy Exploratory Oncology Research and Clinical Trial Center National Cancer Center Kashiwa Japan
2. Second Department of Internal Medicine Faculty of Medical Sciences University of Fukui Eiheiji‐cho Japan
3. Division of Pediatric Oncology National Cancer Center Hospital East Kashiwa Japan
4. Division of Pediatric Oncology National Cancer Center Hospital Tokyo Japan
5. Department of Pediatric Hematology and Oncology Osaka City General Hospital Osaka Japan
6. Department of Pediatric Surgery Kyushu University Hospital Fukuoka Japan
7. Department of Anatomic Pathology Graduate School of Medical Sciences Kyushu University Fukuoka Japan
8. Department of Pediatrics Hokkaido University Sapporo Japan
9. Clinical Research Support Office National Cancer Center Hospital East Kashiwa Japan