Cognitive outcome in children and adolescents treated for acute lymphoblastic leukaemia with chemotherapy only

OBJECTIVE To examine cognitive outcome in children and adolescents with acute lymphoblastic leukaemia (ALL) in remission, treated with central nervous system prophylactic chemotherapy only. METHOD Thirty-five children and adolescents, age 8.4-15.3 years in long-term remission from ALL, 4.2-12.4 years post diagnosis, without relapse and no pre-diagnosis history of neurodevelopmental disorder were compared with 35 healthy controls matched for gender and age, on measures of intellectual functioning Wechsler Intelligence Scale for Children-Third Edition (WISC-III). RESULTS All but two of the ALL survivors treated by chemotherapy only obtained WISC-III Total Intelligence Quotient (IQ) scores in the normal range (M = 95.3), but their scores were significantly below levels for their matched controls and below normative standards for WISC-III. The difference between patients and controls was significant at the p < 0.001 level for the following measures: Total IQ, Verbal IQ, Verbal Comprehension Index, Freedom from Distraction Index and three verbal subtest scores. CONCLUSION The results indicate long-term sequelae in global cognitive functions, and indicate that verbal function, processing speed, attention and complex visual-spatial problem solving may be affected in the chemotherapy only group.