Our Partners Radiooncology / Medical Physics, Department of Oncology, Aarhus University, Denmark Advanced Radiation Oncology Department, Istituto di Ricovero e Cura a Carattere Scientifico Sacro Cuore Don Calabria, Negrar di Valpolicella, Verona, Italy European Radiosurgery Center Munich Division of Radiation Physics, Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA Section for Medical Physics, Department of Radiation Oncology, Erasmus MC Daniel den Hoed Cancer Centre, Netherlands Radiooncology / Medical Physics, Department of Radiooncology, Heidelberg University / Heidelberg University Hospital, Germany Department of Radiation Oncology, UZ Leuven, Belgium Department of Radiation Oncology, University Hospital Zurich, Switzerland