Intellectual and academic achievement status after CNS relapse: a retrospective analysis of 40 children treated for acute lymphoblastic leukemia.

We determined the intellectual and academic status of 40 children with acute lymphoblastic leukemia who had experienced a primary isolated relapse in the CNS by analyzing the results of psychoeducational tests administered a median of 6.1 years after the relapse. Mean scores for full-scale IQ (87.5), verbal IQ (86.7), performance IQ (90.3), as well as academic achievement in reading (89.8), spelling (83.9), and mathematics (83.5) were significantly below normal expectations for age. Twenty percent of the group were mentally retarded and were receiving special educational assistance. The best clinical predictors of full-scale IQ were the number of radiation therapy courses, age, and the presence or absence of cerebral pathology as measured by computed tomography (CT). Children who were younger at the time of treatment, who received two courses of radiation therapy, and who had clinical seizures and structural abnormalities of the brain as detected by CT had the poorest psychological outcome. Although the psychoeducational consequences of CNS relapse and its attendant treatment are significant, these must be balanced by consideration of the relatively low probability of long-term survival without aggressive therapy. Recognition of this type of delayed morbidity with systematic surveillance and prompt attempts at rehabilitation may decrease or at least minimize these sequelae.