Geographical pathology of acute lymphoblastic leukemia in Iran with evaluation of incidence trends of this disease using joinpoint regression analysis

Abstract

Background: The aim of present study is to determine the spatial-temporal epidemiology of acute lymphoblastic leukemia (ALL) in Iranian children. Methods: This ecological study was performed using an exploratory mixed design. The study population consists of 3769 children with ALL who were reported in the National Cancer Registry Program of Iran from 2006 to 2014. Data analysis was conducted using Mann-Whitney U, joinpoint regression analysis, Global Moran's I and Anselin Local Moran's I. Results: The average annual incidence rate of ALL was 2.25 per 100 000 children under 15 years of age during the study period, which was 1.37 times higher in males. The average annual percentage change (AAPC) of the disease was 7.1%, which is higher than that of developed countries. The incidence of ALL was higher in spring and summer and its peak incidence was at the age of 2-5. Spatial autocorrelation of the ALL was 0.358 and significant (P value <0.001). The high-risk cluster of ALL was identified in Fars and Kohgiluyeh and Boyer-Ahmad provinces and the low-risk cluster in Kermanshah, Zanjan and Kurdistan provinces. Conclusion: The incidence of ALL is on rise in Iranian children and appropriate healthcare services are required to prevent new cases of this disease in high-risk areas.