Incidence rates of childhood leukemia, lymphoma, and central nervous system and brain tumor from 1996-2002 birth cohorts in Taiwan

Background The objective of this study was to estimate the incidence rates of top three childhood cancers during 7-13 years of follow-up: leukemia, central nervous system (CNS) and brain cancer, and lymphoma from birth cohorts of 1996-2002 in Taiwan. Methods We conducted a retrospective cohort study consisting of 1996-2002 birth cohorts. The datasets of the study were from Taiwan National Health Insurance Research Database (NHIRD). The childhood cancer cases were identified from datasets of severe illness registry. We calculated incidence rates of leukemia, lymphoma, and CNS and brain tumor and estimated incidence rate ratios to evaluate the independent effects of gender, year of birth cohort, insurance premium and residential area using Poisson regression analysis. Results A total of 1003 leukemia, 260 lymphoma, and 578 CNS and brain tumor patients were identified, and the incidence rates (per 10⁵ person-year) of these corresponding childhood cancers were 4.81, 2.44 and 2.77, respectively. The multivariable-adjusted incidence rate of lymphoma was significantly higher in boys than girls. For leukemia, the 2002 birth cohort was associated with higher risk compared to 1996 birth cohort. For CNS and brain tumor, the 2005 birth cohort and Southern area were associated with a higher risk. Conclusions The incidence rates of childhood leukemia, lymphoma, and CNS and brain tumor in Taiwan were similar to those of previous studies. Leukemia was the most common childhood cancer. Boys were more likely to develop cancers compared with girls.