Assessing changes in brain structure in new-onset children with acute lymphoblastic leukemia.

Background: Brain structure injury was presented in acute lymphoblastic leukemia (ALL) after treatment; however, its alterations in new-onset stage are still unclear. We aim to explore white matter (WM) and grey matter (GM) alterations using surface-based morphometry (SBM) and tract-based spatial statistics (TBSS) in new-onset pediatric ALL.

Methods: Thirty-five ALL and 33 typically developing (TD) children were prospectively recruited and underwent three-dimensional T1-weighted and diffusion tensor (DTI) imaging. DTI metrics, cortical GM features, and deep GM nuclei volume were compared between groups differences.

Results: In ALL, the only increased FA in the body of corpus callosum (P_{FWE-corrected} = 0.023) and left superior corona radiata (P_{FWE-corrected} = 0.045) were presented. Relative to TDs, pediatric ALL presented a significant decrease in cortical surface area (CSA), thickness (CT), and volume in orbital gyri, supramarginal gyrus, middle temporal gyrus, and superior temporal gyrus (all CWP = 0.01). Additionally, increased CT and CSA were found in lingual gyrus and left sulcus intermedius primus, respectively (all CWP = 0.01). Smaller volumes in pediatric ALL were observed in bilateral thalamus, caudate, hippocampus, and right putamen (P_{FDR-corrected} < 0.05).

Conclusion: Widespread brain structural abnormalities were found in new-onset pediatric ALL, which suggest disease itself can cause brain structural injury.

Impact: This study revealed the altered white matter integrity and gray matter morphology characteristics in childhood acute lymphoblastic leukemia on new-onset stage. It is suggested that there may be structural impairment before chemotherapy. MRI is a sensitive way for early detection on brain structural damage in childhood acute lymphoblastic leukemia.