Purpose: Neurocognitive impairment is frequently observed among survivors of childhood acute lymphoblastic leukemia (ALL) within the domains of attention, working memory, processing speed, executive functioning and learning and memory. However, few studies have characterized the trajectory of treatment-induced changes in neurocognitive function beginning in the first months of treatment, to test whether early changes predict impairment among survivors. If correct, we hypothesize that those children who are most susceptible to early impairment would be ideal subjects for clinical trials testing interventions designed to protect against treatment-related neurocognitive decline.
Methods: In this pilot study, we prospectively assessed neurocognitive functioning (attention, working memory, executive function, visual learning, and processing speed), using the Cogstate computerized battery at six time points during the 2 years of chemotherapy and 1 year post treatment enrolled on or as per Dana-Farber Cancer Institute ALL Consortium protocol 11-001; NCT01574274.
Results: 43 patients with ALL consented to serial neurocognitive testing. Of the 31 participants who remained on study through the final time point, one year after completion of chemotherapy, 28 (90%) completed at least five of six planned Cogstate testing timepoints. Performance and completion checks indicated a high tolerability (≥88%) for all subtests. One year after completion of treatment, 10 of 29 patients (34%) exhibited neurocognitive function more than 2 sd below age-matched norms on one or more Cogstate subtests. Conclusions: Serial collection of neurocognitive data (within a month of diagnosis with ALL, during therapy and one year post treatment) is feasible and informative for evaluating treatment-related neurocognitive impairment.