Using functional near-infrared spectroscopy to explore neurocognitive function in adult survivors of childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Due to the drastic increase in survivor rate over the last 50 years, long lasting treatment effect on moods and neurocognitive function has become a present issue. Most studies of late effects of treatment of ALL survivors investigate patients in their adolescents. This pilot study aims to identify measurements for evaluating late effect of childhood ALL survivors regarding neurocognitive and mood problems in adulthood. ALL survivors who received neurotoxic treatment with high-dose methotrexate and cranial radiotherapy (Chemo+CRT) (n=10) and ALL survivors only treated with high-dose methotrexate (Chemo) (n=10), plus age and sex match controls (n=20) where recruited to the study. The study protocol involved questionnaires, neurocognitive tests and optical brain imaging with functional near infrared spectroscopy (fNIRS) over the frontal and parietal cortex. The fNIRS results indicate a reduced involvement of the parietal cortex during conflict processing for the ALL survivors compared to controls. The study protocol shows promising results for identifying subgroups that suffers from neurocognitive and mood problems and we aim to expand upon it in a larger study. As our results indicate increased challenges among female ALL survivors, especially pathological fatigue, anxiety, and information processing, it is important to explore in future investigations the interplay between the risk of hormonal interaction with chemotherapy during development and occupational and social pressure during adulthood.