Long-term psychological effects of childhood leukemia and its treatment.

We report the results of a 5-year follow-up of the cognitive development of 19 survivors of acute lymphoblastic leukemia, all of whom received 24 Gy cranial irradiation and a course of intrathecal methotrexate. Assessment was made before radiotherapy and annually thereafter. Cognitive impairment was found to be transient in children who did not manifest somnolence who were under 5 years at the time of treatment. Despite having normal IQs and normal CT scans, 9 of 18 survivors in continuous complete remission were having learning problems at school 5 years after diagnosis. Assessment of their intellectual and memory functions revealed that as compared with matched healthy children, patients had lowered IQs but also had a specific auditory learning deficit independent of IQ. Long-term memory was found to be impaired for verbal auditory but not for verbal visual material. Results are discussed in terms of possible remediation of the learning disability.