Dr. Monica C. Munthe-KaasPediatric and Adolescent Oncology and HematologyDivision of Paediatric and Adolescent Medicine Oslo University Hospital Rikshospitalet Dr. Lars O. BaumbuschDepartment of Pediatric Research Division of Paediatric and Adolescent Medicine Oslo University Hospital Rikshospitalet Postal address: P. O. Box 4950 Nydalen, N-0424 Oslo, Norway Street address: Sognsvannsveien 20, 0372 Oslo, Oslo University Hospital, Norway Phone: +47 23 07 27 90 Fax: +47 23 07 27 80, Switchboard: +47 22 93 40 00