| Affiliation: | 1. Department of Pediatrics, Hematology, Oncology and Endocrinology, Medical University, Gdansk, Poland;2. Department of Pediatric Surgery, Marciniak Hospital, Wroclaw, Poland;3. Department of Pediatric Surgery, Medical University, Katowice, Poland;4. Department of Oncology, The Children's Memorial Health Institute, Warsaw, Poland;5. Department of Oncology and Hematology, Medical University, Szczecin, Poland;6. Department of Bone Marrow Transplantation, Oncology and Hematology, Medical University, Wroclaw, Poland;7. Department of Oncology and Hematology, Medical University, Zabrze, Poland;8. Department of Oncology and Hematology, Medical University, Bydgoszcz, Poland;9. Department of Pediatric Surgery, Medical University, Poznan, Poland |
