Affiliation: | 1. Department of Paediatrics, Aarhus University Hospital, Palle Juul‐Jensens Boulevard 99, Aarhus N, Denmark;2. Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen, Denmark;3. Department of Clinical Sciences, Paediatric Oncology and Haematology, Sk?ne University Hospital, Lund University, Lund, Sweden;4. Finnish Cancer Registry, Pieni Roobertinkatu 9, Helsinki, Finland;5. Department of Paediatrics, University of Helsinki and Helsinki University Hospital, Helsinki, Finland;6. Faculty of Medicine, Laeknagardur, University of Iceland, Reykjavik, Iceland;7. The Icelandic Cancer Registry, Skogarhlid 9, PO Box 5420, Reykjavik, Iceland;8. Cancer Registry of Norway, P.O. Box 5313, Majorstuen, Oslo, Norway;9. Department of Paediatrics, Oslo University Hospital, Postboks 4950 Nydalen, Oslo;10. Medical Faculty, University of Oslo, P.O box 1078, Blindern, Oslo;11. Department of Paediatrics and Adolescent Medicine, Rigshospitalet, Blegdamsvej 9, Copenhagen, Denmark |