1. Department of Pediatric Hematology, Oncology and Transplantology Medical University of Lublin University Children Hospital Lublin Poland
2. Department of Pediatric Hematology, Oncology and Transplantology Laboratory of Genetic Diagnostics Medical University of Lublin University Children Hospital Lublin Poland
3. Department of Pediatric Hematology and Oncology Collegium Medicum Nicolaus Copernicus University Bydgoszcz Poland
4. Department of Pediatric Oncology, Hematology and Transplantology Medical University Poznań Poland
5. Department of Pediatric Hematology, Oncology and Transplantology Medical University Poznań Poland
6. Department of Transplantation Children’s University Hospital Clinical Immunology and Transplantation Polish‐American Institute of Pediatrics Jagiellonian University Medical College Krakow Poland
7. Department of Pediatric Transplantology, Hematology and Oncology Medical University Wrocław Poland