1. Department of Haematology and Oncology, German Armed Forces Hospital of Ulm, Ulm, Germany
2. Department of Pathology and Molecular-Pathology, German Armed Forces Hospital of Ulm, Ulm, Germany
3. Department of Haematology and Oncology, University Hospital of Schleswig-Holstein, Luebeck, Germany
4. Department of Neurosurgery, German Armed Forces Hospital of Ulm, Ulm, Germany
5. Department of Neurosurgery, University Hospital of Schleswig-Holstein, Luebeck, Germany