Spatial Analysis of Childhood Cancers in Iran during ۲۰۰۵-۲۰۱۳

Introduction: Childhood cancers are among the leading causes of disease-related child mortality worldwide. Previous studies have shown that the growth and spread of childhood cancers differ among communities; therefore, this study aimed to analyze the spatial trend of such cancers incidence in Iran during ۲۰۰۵-۲۰۱۳. Material and Methods: A total of ۱۷۱۵۵ incident malignant ۰-۱۴ years old cases during ۲۰۰۵-۲۰۱۳ recorded by the Iran National cancer registry were included in this analysis. Age specific and age-standardized incidence rates (ASIR) were reported for province of residence, sex and three time periods. To explore geographical correlation of ASIR, adaptive spatiotemporal smoothing model was applied. Relative Risk (RR) estimation in all provinces at each time period was provided. Results: Majority of the studied cases were males (۵۶.۷%), half of them being ۰-۴ years old. The overall age-standardized incidence rate (ASIR) was estimated as ۷۹.۷۶ ,۱۲۹.۰۷, and ۱۳۷.۹۲ per million person-years respectively. Leukemia, other malignant and Lymphoma & related groups had the highest ASIR with ۳۲.۴۱, ۲۱.۰۷ and ۱۳.۴۰, respectively. Almost all five common cancers had increasing trend in most of the provinces through time periods. Changes of childhood cancers during time periods were statistically significant for all cancers combined and by gender. Conclusion: Increasing age-standardized incidence rate during studied time was observed. Apart from the increasing trend of cancers worldwide, this can be justified by improvement in registries and also availability of more sophisticated and precise technologies for early diagnosis.

Keywords:

Childhood Cancer , Spatial Analysis , Registry , Iran