[1] Univ Athens, Sch Med, Dept Hyg Epidemiol & Med Stat, GR-11527 Athens, Greece
[2] Natl Canc Inst, Natl Canc Registry Ukraine, Kiev, Ukraine
[3] Childhood Canc Subregistry Belarus, Belarusian Res Ctr Pediat Oncol Hematol & Immunol, Minsk, BELARUS
[4] Natl Oncol Hosp, Bulgarian Natl Canc Registry, Sofia, Bulgaria
[5] Inst Publ Hlth Serbia, Belgrade, Serbia
[6] Izmir Canc Registry, Izmir Hub, Izmir, Turkey
[7] Hacettepe Univ, Inst Publ Hlth, Ankara, Turkey
[8] Portuguese Oncol Inst Porto, North Reg Canc Registry Portugal NORTH, Oporto, Portugal
[9] Croatian Inst Publ Hlth, Croatian Natl Canc Registry, Zagreb, Croatia
[10] Canc Registry Republ Slovenia, Inst Oncol, Ljubljana, Slovenia
[11] Inst Portugues Oncol Coimbra Francisco Gentil EPE, Registo Oncol Reg Ctr, Coimbra, Portugal
[12] Minist Hlth, Hlth Monitoring Unit, Cyprus Canc Registry, Nicosia, Cyprus
[13] Inst Publ Hlth, Epidemiol, Timisoara 300226, Romania
[14] Oncol Inst Ion Chiricuta, Reg Canc Registry Cluj, Cluj Napoca, Romania
[15] Mitera Childrens Hosp, Dept Oncol, Athens, Greece
[16] Aristotel Univ Thessaloniki, Dept Pediat 2, AHEPA Gen Hosp, Thessaloniki, Greece
[17] Hippokrateion Hosp, Dept Pediat Hematol & Oncol, Thessaloniki, Greece
[18] Aghia Sophia Childrens Hosp, Dept Pediat Haematol Oncol, Athens, Greece
[19] Pan & Agl Kyriakou Childrens Hosp, Dept Pediat Hematol Oncol, Athens, Greece
[20] Univ Crete, Univ Hosp Heraklion, Dept Pediat Hematol Oncol, Iraklion, Greece
[21] Univ Athens, Sch Med, Aretaie Hosp, Dept Radiol 1, GR-11527 Athens, Greece
[22] Univ Hosp Heraklion, Dept Neurosurg, Iraklion, Crete, Greece
[23] G Gennimatas Gen Hosp, Dept Neurosurg, Athens, Greece
[24] Hygeia Hosp, Dept Pathol, Athens, Greece
[25] Univ Athens, Sch Med, Radiotherapy Unit, Dept Radiol 2, Athens, Greece
[26] Univ Athens, Sch Med, Dept Pathol, Athens 11528, Greece
[27] Mitera Childrens Hosp, Dept Neurosurg, Athens, Greece
[28] St Lukes Hosp, Dept Neurosurg, Thessaloniki, Greece
[29] Univ Athens, Sch Med, Aghia Sophia Childrens Hosp, Haematol Oncol Unit,Dept Pediat 1, GR-11527 Athens, Greece
[30] Int Agcy Res Canc, Sect Canc Surveillance, F-69372 Lyon, France