1. Department I of Internal Medicine and Center of Integrated Oncology Aachen, Bonn, Cologne, Düsseldorf, German CLL Study Group, Faculty of Medicine and University Hospital of Cologne, University of Cologne, Cologne, Germany
2. Clinic for Hematology and Stem Cell Transplantation, West German Cancer Center, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
3. Department of Oncogeriatrics, Center for Geriatric Medicine, St. Marien-Hospital, Cologne, Germany
4. Division of CLL, Department of Internal Medicine III, Ulm University, Ulm, Germany
5. Department of Hematology, Oncology, Immunology, Palliative Care, Infectious Diseases and Tropical Medicine, German CLL Study Group, Munich Clinic Schwabing, Munich, Germany
6. The Francis Crick Institute, London, United Kingdom
7. UCL Cancer Institute, University College London, London, United Kingdom