In this study we aimed to evaluate incidence rates and family risk of the most common childhood cancers, tumours in the central nervous system (CNS) and leukaemia among individuals from Norway and individuals with Scandinavian ancestry living in Utah.
MethodsWe used the Utah Population Database and the Norwegian National Population Register linked to Cancer registries to identify cancers in children born between 1966 and 2015 and their first-degree relatives. We calculated incidence rates and hazards ratios.
ResultsThe overall incidence of CNS tumours increased with consecutive birth cohorts similarly in Utah and Norway (both p<0.001). Incidence rates of leukaemia were more stable and similar in both Utah and in Norway with 4.6/100,000 person-years among children (<15 years) born in the last cohort. A family history of CNS tumours was significantly associated with risk of childhood CNS tumours in Utah HR= 3.05(95% CI 1.80-5.16) and Norway HR= 2.87(95% CI 2.20-3.74). In Norway, children with a first-degree relative diagnosed with leukaemia had high risk of leukaemia (HR= 2.39, 95% CI 1.61-3.55).
ConclusionDespite geographical distance and assumed large life style differences, two genetically linked paediatric populations show similar incidences of CNS tumours and leukaemia in the period 1966-2015. CNS tumours and leukaemia aggregated in families in both countries.