Increasing incidence rates of childhood malignant diseases in Sweden during the period 1960-1998

Abstract

We analysed the trends in incidence rates of childhood cancer in Sweden. All cases of malignant diseases and benign brain tumours in children, 0-14 years old, reported to the Swedish Cancer Registry 1960 to 1998 were included, n=9298. Cases were classified according to the International Classification of Childhood Cancer. Average annual change in incidence rate was calculated to +1.01%, (95% confidence interval CI=0.80, 1.22). An increase in incidence rate per year was found for leukaemia, +0.85% (95% CI=0.42, 1.28), lymphomas +1.87% (95% CI=1.17, 2.58), CNS (central nervous system) tumours +1.45% (95% CI=1.02, 1.88), sympathetic nervous system tumours +1.61% (95% CI=0.79, 2.44), hepatic tumours +2.62% (95% CI=2.02, 3.21), and germ cell and gonadal tumours +1.21% (95% CI=0.23, 2.19). Of the CNS tumours, significant changes were seen for low-grade glioma/astrocytoma +2.10% (95% CI=1.41, 2.80), benign brain tumours +3.77% (95% CI=2.47, 5.10), and PNET/medulloblastoma +1.96% (95% CI=0.48, 3.46). Changes in diagnostic criteria and better diagnostic tools may have contributed to these results.