1. Department of Pediatric Oncology and Hematology, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Krakow, Poland
2. Department of Pediatric Oncology and Hematology, University Children Hospital, 30-683 Krakow, Poland
3. Department of Medical Genetics, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Krakow, Poland
4. Department of Clinical Immunology, Institute of Pediatrics, Jagiellonian University Medical College, 30-663 Krakow, Poland
5. Department of Pediatrics, Oncology, Hematology and Transplantology, Medical University of Warsaw, 02-091 Warszawa, Poland
6. Department of Pediatric Oncology, Hematology and Transplantology, Poznan University of Medical Sciences, 60-572 Poznan, Poland
7. Department of Bone Marrow Transplantation, Pediatric Oncology and Hematology, Medical University of Wroclaw, 50-556 Wroclaw, Poland
8. Department of Pediatric Oncology and Hematology, Medical University of Bialystok, 15-089 Bialystok, Poland
9. Department of Pediatric Hematology, Oncology and Transplantology, 20-093 Lublin, Poland
10. Department of Pediatrics, Hematology and Oncology, Medical University of Gdansk, 80-210 Gdansk, Poland
11. Department of Pediatrics, Oncology and Hematology, Medical University of Lodz, 91-738 Lodz, Poland
12. Department of Pediatric Hematology and Oncology, Zabrze, Medical University of Silesia, 40-055 Katowice, Poland
13. Department of Pediatric Hematology and Oncology, Regional Polyclinic Hospital in Kielce, 25-736 Kielce, Poland
14. Department of Pediatrics and Hematology and Oncology, Province Children’s Hospital, 10-561 Olsztyn, Poland
15. Department of Paediatrics, Hemato-Oncology and Gastroenterology, Pomeranian Medical University in Szczecin, 71-252 Szczecin, Poland
16. Department of Pediatric Hematology and Oncology, Collegium Medicum, Nicolaus Copernicus University Torun, Bydgoszcz, 85-094 Bydgoszcz, Poland