VU University Amsterdam - Department of Haematology, VU University Amsterdam, University of Groningen - Department of Hematology and Oncology, Erasmus University Rotterdam (EUR) - HOVON Data Center, Utrecht University - University Medical Center (Utrecht), Erasmus University Rotterdam (EUR) - Cancer Institute, KU Leuven - University Hospitals Leuven, University of Groningen, Leiden University - Leiden University Medical Center (LUMC), Leiden University - Leiden University Medical Center (LUMC), Oncology Center Isala, Canisius-Wilhelmina Ziekenhuis, Admiraal de Ruijter Hospital, University of Groningen - University Medical Center Groningen (UMCG), Radboud University Nijmegen - Radboud University Medical Center, Amsterdam UMC, Vrije Universiteit Amsterdam - Department of Radiology & Nuclear Medicine, VU University Amsterdam - Department of Hematology, VU University Amsterdam and University of Amsterdam, Academic Medical Center, Department of Hematology