1. Department of Medicine I Hematology and Oncology, Faculty of Medicine and Medical Center, University of Freiburg , 79106 Freiburg , Germany
2. Comprehensive Cancer Center Freiburg, Faculty of Medicine and Medical Center, University of Freiburg , 79106 Freiburg , Germany
3. Clinical Trials Unit, Biometry and Statistics, Faculty of Medicine, University of Freiburg , 79106 Freiburg , Germany
4. Department of Medicine, Medical Center University of Freiburg, Faculty of Medicine, Institute for Exercise and Occupational Medicine, University of Freiburg , 79106 Freiburg , Germany