1 Department for Oncology-Haematology, Martin Luther University Halle-Wittenberg, Ernst Grube Strasse 40, Halle 06120, Germany.
2 Department of Oncology, Haematology, Stem Cell Transplantation with the Section Pneumology, Hubertus Wald Tumour Centre, University Cancer Centre Hamburg, Martinistrasse 52, Hamburg 20246, Germany.