aDepartment of Haematology, Vall d’Hebron Institute of Oncology, University Hospital Vall d’Hebron, Barcelona, Spain

bDepartment of Haematology, Beatson West of Scotland Cancer Centre, Glasgow

cDepartment of Haematology, University College London Hospital, London, UK

Correspondence to Kate Cwynarski, University College London Hospital, 3rd Fl, West, 250 Euston Rd, London NW1 2PG, UK. E-mail: [email protected]