1. Department of Oncology, Rigshospitalet, Copenhagen, Denmark;
2. Niels Bohr Institute, Copenhagen University, Copenhagen, Denmark;
3. Radiotherapy Research Unit, Department of Oncology, Herlev and Gentofte Hospital, Herlev, Denmark;
4. German Cancer Research Center (DKFZ), Heidelberg, Germany;
5. Faculty of Health and Medical Science, Copenhagen University, Copenhagen, Denmark