1. Department of Palliative Medicine, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
2. Department of Palliative Medicine, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
3. University of Cologne, Faculty of Medicine and University Hospital, Center for Integrated Oncology Aachen Bonn Cologne Dusseldorf, Cologne, Germany
4. Department of Palliative Medicine, LMU Klinikum, Ludwig-Maximilians-University, Munich, Germany