1. Department I of Internal Medicine and German CLL Study Group; Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD) University of Cologne, Faculty of Medicine and University Hospital 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 Internal Medicine III University Hospital Ulm Ulm Germany
4. Practice for Hematology and Oncology UnterEms Leer Germany
5. Practice for Hematology and Oncology Bethanien Frankfurt/Main Germany
6. Practice for Hematology and Oncology Pasing and Fürstenfeldbruck Munich Germany
7. Department of Internal Medicine II Campus Kiel, University of Schleswig‐Holstein Kiel Germany
8. Department of Hematology, Oncology, Immunology, Palliative Care, Infectious Diseases and Tropical Medicine Munich Clinic Schwabing Munich Germany