1. Department of Pediatric Hematology, Oncology and Transplantology, Medical University, Lublin, Poland
2. Department of Hematology and Pediatrics, Children's Hospital, Warsaw, Poland
3. Department of Pediatric Oncology and Hematology, Children's University Hospital, Kraków, Poland
4. Department of Pediatric Transplantology, Oncology, Hematology, Medical University, Wrocław, Poland
5. Department of Pediatric Oncology, Hematology and Transplantology, Medical University, Poznań, Poland
6. Department of Pediatrics, Hematology, Oncology and Endocrinology, Medical University, Gdańsk, Poland
7. Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University, Łódź, Poland
8. Department of Pediatrics, Hematology and Oncology, Collegium Medicum, Bydgoszcz, Poland
9. Department of Pediatrics, Hematology and Oncology, Medical University, Zabrze, Poland
10. Department of Pediatric Oncology, Hematology, Medical University, Białystok, Poland
11. Department of Pediatrics, Hematology and Oncology, Medical University, Szczecin, Poland
12. Department of Pediatric Oncology, Hematology and Chemotherapy, Medical University, Katowice, Poland
13. Department of Pediatric Oncology and Hematology, Children's Hospital, Kielce, Poland