Impact of Subventricular Zone Invasion on Preoperative Cognitive Decline in Patients with Diffuse Glioma

To assess the impact of subventricular zone (SVZ) invasion on neurocognitive dysfunction in patients with diffuse glioma.

We analyzed neuropsychological assessments of 129 patients with World Health Organization grade 2-4 treatment-naive diffuse glioma (2017-2023). Univariable and multivariable regression analyses were used to identify factors associated with cognitive dysfunction. A nomogram was developed to predict cognitive impairment probabilities, and the model's predictive accuracy was assessed using area under the curve. Statistical analyses were performed using IBM SPSS 20 and R. A P -value of <.05 was considered significant.

SVZ invasion (SVZ+) was present in 64 patients and was linked to more cognitive deficits compared with SVZ- (65 patients). In low-grade gliomas, SVZ+ increased risks of language and visual learning impairments, whereas in high-grade tumors, it heightened language and auditory learning vulnerabilities. In right hemispheric tumors, SVZ+ conferred worse global cognition, executive, and language function; in left hemispheric tumors, SVZ+ increased risks of language and auditory learning impairments. Frontal horn of SVZ+ was related to working memory decline, and body part of SVZ+ was related to emotional deficits. SVZ+ was an independent predictor of cognitive decline alongside age, T2 volume, and World Health Organization grade. A final model and nomogram composed of age, T2 volume, and SVZ invasion achieved moderate predictive accuracy (area under the curve 0.749) for cognitive dysfunction.

SVZ invasion affects preoperative neurocognitive function independent of tumor laterality and grade, with distinct SVZ subregions associated with specific cognitive impairments. These findings highlight the need for precise tumor mapping considering the SVZ to evaluate neurocognitive outcomes and consider preventive or rehabilitative interventions.