1. Depts of Pediatric Hematology, Amsterdam University Medical Centers, Location VUMC, Amsterdam, The Netherlands;
2. Clinical Chemistry, Amsterdam University Medical Centers, Location VUMC, Amsterdam, The Netherlands;
3. Department of Hematology-Oncology, Pontifical Catholic University of Chile, Santiago, Chile;
4. Department de Bioquímica i Biologia Molecular, Universitat de Barcelona, Barcelona, Spain;
5. Princess Maxima Center for Pediatric Cancer, Utrecht, and SKION, The Netherlands;
6. Emma's Children's Hospital, Amsterdam UMC, Location VUMC, Pediatric Oncology, Amsterdam, The Netherlands;
7. Reumatology, Amsterdam University Medical Centers, Location VUMC, Amsterdam, The Netherlands;
8. Laboratory Medical Oncology, Amsterdam University Medical Centers, Location VUMC, Amsterdam, The Netherlands;
9. Department of Biochemistry, Medical University of Gdansk, Gdansk, Poland