1. Department of Medical Physics, Vejle Hospital, Vejle, Denmark;
2. MAASTRO Clinic, School of Oncology and Developmental Biology, Maastricht University, Maastricht, the Netherlands;
3. Danish Colorectal Cancer Centre South, Vejle Hospital, and Institute of Regional Health Research, University of Southern Denmark, Denmark;
4. Department of Oncology, Vejle Hospital, Vejle, Denmark;
5. Leeds Institute of Cancer and Pathology, University of Leeds, and Leeds Cancer Centre, St. James' University Hospital, Leeds, UK