Background: Children with acute lymphoblastic leukemia (ALL) are prone to neurotoxicity and consequently neurocognitive function impairment mainly due to undergoing different treatment modalities. In the current investigation, neurocognitive function of children with ALL was compared to that of healthy children.
Materials and Methods: In this cross-sectional study, 155 ALL and 155 age- matched healthy children in Shiraz, Southern Iran, were included and evaluated using Continuous Performance Test (CPT). 
Results: Mean age of the patients was 9.9± 2.4 years. The number of wrong responses and duration of response did not lead to significant difference between healthy and affected children. In the age group less than 12 years old, the frequency of no-response was higher in the case group compared to control group both in boys and girls (P = 0.012, P = 0.006 respectively). In addition, in male patients younger than 12 years old, the number of correct responses was significantly less than that of  controls (P = 0.010). Patients underwent concurrent radiotherapy and chemotherapy needed significantly more time for responding compared to patients in whom chemotherapy were discontinued and were in remission (P=0.001).
Conclusion: Based on the results, ALL children younger than 12 years old showed some defects in cognitive function. Moreover, it was more prominent in young boys compared to young girls. Regardless of the type of treatment regimens, early detection of neurocognitive disorders should be warranted in this high-risk population with more focus on boys and younger children. Psychological support and appropriate interventions can help improve cognitive function, reduce the disruption of education, and enhance the social and family relationships.