1. Department of Oncology, Division of Pediatric and Adolescent Medicine Oslo University Hospital Rikshospitalet Oslo Norway
2. Department of Pediatric Research, Division of Pediatric and Adolescent Medicine Oslo University Hospital Rikshospitalet Oslo Norway
3. Department of Pediatrics Haukeland University Hospital Bergen Norway
4. Department of Pathology, Section for Neuropathology Oslo University Hospital Oslo Norway
5. Department of Pathology, Faculty of Medicine University of Oslo Oslo Norway
6. Department of Pharmacology, Medical Faculty University of Latvia Riga Latvia
7. Department of Pathology Haukeland University Hospital Bergen Norway
8. Department of Pathology St. Olavs Hospital Trondheim Norway
9. Department of Pediatrics University Hospital of North‐Norway Tromsø Norway
10. Faculty of Health Science The Arctic University of Norway Tromsø Norway
11. Department of Pathology University Hospital of North‐Norway Tromsø Norway
12. Department of Pediatrics St. Olavs Hospital Trondheim Norway
13. Faculty of Medicine and Health Sciences, Department of Clinical and Molecular Medicine NTNU Trondheim Norway