1. Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
2. Department of Internal Medicine III, Ludwig-Maximilians University Hospital, Munich, Germany
3. Department of Pediatric Hematology, Oncology and Clinical Immunology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
4. Department of Radiation Oncology, University Hospital Erlangen, Erlangen, Germany
5. Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany
6. Department of Radiology, Ludwig-Maximilians University Hospital, Munich, Germany
7. Faculty of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands