1. Department of Hematology; VU Institute of Cancer and Immunology (V-ICI), Cancer Center Amsterdam (CCA), VU University Medical Center; Amsterdam Netherlands
2. Department of Hematology; University Medical Center Groningen; Groningen Netherlands
3. Department of Hematology; Radboud University Nijmegen Medical Center; Nijmegen Netherlands
4. Department of Epidemiology and Biostatistics; VU University Medical Center; Amsterdam Netherlands
5. Functional Unit of Haematology; Azienda Ospedaliero Universitaria Careggi, University of Florence; Florence Italy