Role of tumor momentum in neurocognitive deficits among pediatric brainstem glioma prior to treatment: a pilot study.

PURPOSE: To investigate the association between tumor momentum indices and pretreatment neurocognitive function in children with brainstem gliomas (BSGs), and to evaluate their prognostic value for overall survival (OS).

METHODS

This prospective pilot study enrolled 34 treatment-naïve children with histopathologically confirmed BSGs and 30 age-matched healthy controls at Beijing Tiantan Hospital, Capital Medical University. Neurocognitive function was assessed using the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), and emotional-behavioral performance was screened with the Child Behavior Checklist (CBCL). Tumor momentum was characterized by the MRS-derived Cho/Cr ("image momentum") and the Ki-67 proliferative index ("pathological momentum"). Kaplan-Meier analysis was performed to evaluate OS.

RESULTS

Patients scored significantly lower than controls across all WISC-IV composite scores and subtests (p < 0.001). The Cho/Cr ratio was inversely correlated with verbal comprehension (ρ = -0.412, p = 0.015) and independently predicted potential verbal function deficit (OR = 4.281, 95% CI 1.146-15.994, p = 0.031). The Ki-67 index was positively associated with CBCL attention problems in high- versus low-Ki-67 subgroups (p = 0.036). Ki-67 was significantly associated with OS (p = 0.027), whereas neither Cho/Cr nor baseline cognitive status demonstrated prognostic value.

CONCLUSION

Our study provides the first direct evidence that treatment-naïve children with BSGs harbor significant neurocognitive impairment assessed by a standardized intelligence scale. The Cho/Cr ratio and the Ki-67 index capture complementary dimensions of tumor biology: the former may serve as a non-invasive biomarker for cognitive risk stratification, while the latter retains its established prognostic value for survival.