1. Cochrane Haematology, Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf; Faculty of Medicine and University Hospital Cologne, University of Cologne; Cologne Germany
2. Department I of Internal Medicine; Faculty of Medicine and University Hospital Cologne, University of Cologne; Cologne Germany
3. Department of Hematology and Stem Cell Transplantation; West German Cancer Center, University Hospital Essen, University of Duisburg-Essen; Essen Germany