The incidence of childhood cancer in Australia, 1983-2015, and projections to 2035.

objectivesTo describe changes in childhood cancer incidence in Australia, 1983-2015, and to estimate projected incidence to 2035. DESIGN,

settingPopulation-based study; analysis of Australian Childhood Cancer Registry data for the 20 547 children under 15 years of age diagnosed with cancer in Australia between 1983 and 2015.

main outcome measuresIncidence rate changes during 1983-2015 were assessed by joinpoint regression, with rates age-standardised to the 2001 Australian standard population. Incidence projections to 2035 were estimated by age-period-cohort modelling.

resultsThe overall age-standardised incidence rate of childhood cancer increased by 34% between 1983 and 2015, increasing by 1.2% (95% CI, +0.5% to +1.9%) per annum between 2005 and 2015. During 2011-2015, the mean annual number of children diagnosed with cancer in Australia was 770, an incidence rate of 174 cases (95% CI, 169-180 cases) per million children per year. The incidence of hepatoblastoma (annual percentage change [APC], +2.3%; 95% CI, +0.8% to +3.8%), Burkitt lymphoma (APC, +1.6%; 95% CI, +0.4% to +2.8%), osteosarcoma (APC, +1.1%; 95%, +0.0% to +2.3%), intracranial and intraspinal embryonal tumours (APC, +0.9%; 95% CI, +0.4% to +1.5%), and lymphoid leukaemia (APC, +0.5%; 95% CI, +0.2% to +0.8%) increased significantly across the period 1983-2015. The incidence rate of childhood melanoma fell sharply between 1996 and 2015 (APC, -7.7%; 95% CI, -10% to -4.8%). The overall annual cancer incidence rate is conservatively projected to rise to about 186 cases (95% CI, 175-197 cases) per million children by 2035 (1060 cases per year).

conclusionsThe incidence rates of several childhood cancer types steadily increased during 1983-2015. Although the reasons for these rises are largely unknown, our findings provide a foundation for health service planning for meeting the needs of children who will be diagnosed with cancer until 2035.