Trends in incidence of childhood cancers in the Czech Republic: population-based analysis of national registries (1994–2014)

 Daniela Kodytkova, Viera Bajciova, Denisa Krejčí, Michaela Zapletalova, Vitezslav Dusek, Jiri Jarkovsky, Jan Muzik, Daniel Klimes, Jan Stary, Vratislav Smelhaus, Alena Vrzalova, Iveta Janotova, Jaroslav Sterba, Ladislav Dusek

Abstract:

The purpose of this study is to summarize incidence and trends in the pediatric cancer burden in the Czech Republic over the period 1994–2014. The recently established Childhood Cancer Registry was combined with retrospective data from the Czech National Cancer Registry to analyze the annual patterns of incidence and long-term trends of pediatric cancer patients aged 0–14 years diagnosed between 1994 and 2014. Malignancies were classified according to the International Classification of Childhood Cancer. The distribution of incidence was stratified according to gender, age at diagnosis, type of cancer and geographic area. Annual age-standardized rates were adjusted using the world standard population. Changes over time were quantified as the average annual percentage change. This analysis comprised records of 5,605 children diagnosed with cancer within the period 1994–2014, annually 267 records on average; the overall age-standardized average annual incidence rate was 169 cases per million. Boys were affected more frequently than girls: the M/F crude incidence ratio was 1.2:1. The highest incidence rates were observed for ICCC groups I (27.8%), III (21.8%), II (12.4%) and IV (7.8%); other groups formed 30.2%. There are significant differences in the geographic distribution of incidence between regions. A borderline statistically significant increase (0.6%) in the overall average annual percentage change was detected between 1994 and 2014 (95% CI: 0.01 to 1.12; p = 0.05). This study provides reliable recent information on trends in the incidence of childhood cancers in the Czech Republic.