Neurodevelopmental outcome of infants with acute lymphoblastic leukemia - A children's cancer group report

BACKGROUND. Infants diagnosed with acute lymphoblastic leukemia (ALL) are c onsidered the patient subgroup at the highest risk for central nervous syst em (CNS) disease, both at presentation and as an isolated extramedullary re lapse. In addition, they are highly vulnerable to adverse developmental seq uelae from CNS-directed therapy. METHODS. Thirty patients younger than 12 months at diagnosis (12 males, 18 females) in first hematologic remission were evaluated after completion of ALL therapy (mean age = 62.1 months; standard deviation = 17.2 months; rang e = 38-102 months). CNS-directed treatment included very high dose infusion s of methotrexate (MTX) and intrathecal cytarabine and MTX. Three patients had meningeal leukemia that required additional therapy. Children were admi nistered the McCarthy Scales of Children's Abilities, and parents completed a sociodemographic questionnaire to obtain information about occupation an d education. RESULTS. Mean scores on all 6 cognitive and motor indices of the McCarthy S cales were in the average range (Verbal = 52.0; Perceptual = 53.6; Quantita tive = 49.6; General Cognitive Index [GCI] = 102.1; Memory = 49.2; Motor = 51.0). Score distributions for each neurodevelopmental index were comparabl e to age-based population standards. One patient obtained a GCI that exceed ed 2 standard deviations above the mean; none scored more than 2 standard d eviations below. There was no report of developmental disabilities or neuro logic disorders for any of the patients. Risk factors, including age at dia gnosis, gender, additional CNS-directed treatment, and family socioeconomic status, were not associated with developmental outcome. CONCLUSIONS. Test findings indicated a generally positive neurodevelopmenta l outcome for ALL patients diagnosed in infancy who were treated with Very high dose MTX as CNS-directed therapy. Combined with the reduction in the i solated CNS relapse rate achieved by the Children's Cancer Group (CCG) clin ical trial CCG-107, the results of this study represent a substantial impro vement in neurodevelopmental outcome for very young patients compared with infants Created for ALL in the past. (C) 1999 American Cancer Society.