1. Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany;
2. Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Garching bei München, Germany;
3. Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark;
4. University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität München (LMU Munich), Munich, Germany;
5. Department of Radiology, University Hospital, LMU Munich, Munich, Germany;
6. Optical and Interpretative Astronomy, Max Planck Institute for Extraterrestrial Physics, Garching bei München, Germany;
7. German Cancer Consortium (DKTK), Partner site Munich, Munich, Germany