Long-term effects of cranial radiation therapy on attention functioning in survivors of childhood leukemia

Objective: To retrospectively examine the long-term effects of cranial radiation therapy (CRT) on attention functioning. Methods: Fifty-six survivors of childhood leukemia who had been randomly assigned to a treatment regimen of chemotherapy with or without 1,800 cGy CRT were administered a neuropsychological test battery. Results: Significant differences were found between the irradiated and nonirradiated groups on three of four attentional components. An interaction between treatment type and age at diagnosis was significant on one attentional component. Further, the mean scores of participants irradiated in early childhood were significantly low relative to published norms for age-standard scores on the majority of task variables, while the other groups showed rare deviations from average scores. Conclusions: Findings from this study indicate that early irradiation was associated with significant impairment in attentional filtering, focusing, and automatic shifting.