1. Department of Pediatric Oncology, University Hospital Brno and Masaryk University, Brno, the Czech Republic
2. Department of Hematology, University Hospital Brno and Masaryk University, Brno, the Czech Republic
3. Department of Pathology, University Hospital Brno and Masaryk University, Brno, the Czech Republic
4. Department of Pediatric Oncology, Teaching Hospital OSTRAVA, the Czech Republic