1 Clinic for Internal Medicine C - Haematology and Oncology, Stem Cell Transplantation and Palliative Care, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße, 17475, Greifswald, Germany.
2 Clinic for Internal Medicine C - Haematology and Oncology, Stem Cell Transplantation and Palliative Care, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße, 17475, Greifswald, Germany. william.krueger@med.uni-greifswald.de.