Trends in incidence of childhood cancer in Australia, 1983–2006

BACKGROUND: There are few population-based childhood cancer registries in the world containing stage and treatment data. METHODS: Data from the population-based Australian Paediatric Cancer Registry were used to calculate incidence rates during the most recent 10-year period (1997–2006) and trends in incidence between 1983 and 2006 for the 12 major diagnostic groups of the International Classification of Childhood Cancer. RESULTS: In the period 1997–2006, there were 6184 childhood cancer (at 0–14 years) cases in Australia (157 cases per million children). The commonest cancers were leukaemia (34%), that of the central nervous system (23%) and lymphomas (10%), with incidence the highest at 0–4 years (223 cases per million). Trend analyses showed that incidence among boys for all cancers combined increased by 1.6% per year from 1983 to 1994 but have remained stable since. Incidence rates for girls consistently increased by 0.9% per year. Since 1983, there have been significant increases among boys and girls for leukaemia, and hepatic and germ-cell tumours, whereas for boys, incidence of neuroblastomas and malignant epithelial tumours has recently decreased. For all cancers and for both sexes combined, there was a consistent increase (+0.7% per year, 1983–2006) at age 0–4 years, a slight non-significant increase at 5–9 years, and at 10–14 years, an initial increase (2.7% per year, 1983–1996) followed by a slight non-significant decrease. CONCLUSION: Although there is some evidence of a recent plateau in cancer incidence rates in Australia for boys and older children, interpretation is difficult without a better understanding of what underlies the changes reported.