Are cognitive and educational development affected by age at which prophylactic therapy is given in acute lymphoblastic leukaemia?

Altogether 129 children with acute lymphoblastic leukaemia in remission, all of whom had completed treatment, were assessed using standardised intelligence and attainment tests. A control group of 67 healthy siblings was also assessed. Results showed that the patients were functioning within the average range of intelligence several years after completing treatment but that they had significantly lower intelligence quotients (IQs) than their siblings. Only patients who received cranial irradiation when aged 7 years or more were no different in intelligence from their siblings. Patients who were treated under the age of 3 years were found to have significantly lower IQs than patients who received the same treatment at an older age and a group of healthy children matched for age, sex, and parental occupation. This finding has practical implications for the management and education of younger patients with acute lymphoblastic leukaemia.