FROM JOURNAL OF CLINICAL ONCOLOGY
Survivors of childhood acute lymphoblastic leukemia (ALL) who underwent CNS-directed chemotherapy show significant attention problems that impair their functioning 2 years later, according to a report published online Feb. 8 in the Journal of Clinical Oncology.
The attention problems were isolated from intelligence and academic performance, but they still “significantly and negatively impact real-world functioning,” said Lisa M. Jacola, Ph.D. of the department of psychology and her associates at St. Jude Children’s Research Hospital, Memphis (J Clin Oncol. 2016 Feb 8. [doi: 10.1200/JCO.2015.64.3205 ]).
Intrathecal chemotherapy has largely replaced cranial radiation therapy to protect the CNS in childhood ALL, but most research concerning neurocognitive outcomes after this treatment has been retrospective and has involved small sample sizes. So investigators performed a prospective study using data from an ongoing trial involving a representative cohort of more than 400 patients aged 1-18 years who were treated at a single center during a 7-year period.
These patients were classified as low- or high-risk based on comprehensive biologic and clinical factors, such as blast cell immunophenotype and genotype, presenting clinical features, and early treatment response. They then received intrathecal methotrexate, cytarabine, and hydrocortisone in doses appropriate to their risk status, as well as standardized leucovorin followed by mercaptopurine and vincristine plus dexamethasone.
The researchers focused on the 211 patients who underwent comprehensive neurocognitive assessment 2 years after diagnosis and treatment. “The overall group did not significantly differ from normative expectations on measures of global intelligence (estimated IQ), academic skills (reading, math, or spelling), and learning and memory.” However, half of them were rated as below average on several measures of attention. In addition, caregivers reported a significantly greater than expected frequency of hyperactivity, impulsivity, and learning problems in the children.
This adverse effect was strongest among children who were younger than age 5 at diagnosis and among those at high risk who received more aggressive treatment.
“Our findings … emphasize the importance of routine neurocognitive monitoring of all survivors treated with contemporary therapy.” But early detection will only be helpful if effective interventions are developed to remediate these attention and behavior problems. Research has shown that pharmacologic therapies “have reduced acceptability among survivors of childhood cancer,” so nonpharmacologic approaches would be especially useful, the researchers added.
