CNSC-09. Subventricular Zone Invasion Predicts Poor Neurocognitive Recovery in Low-Grade Glioma Patients

PURPOSE To investigate the longitudinal impact of subventricular zone (SVZ) invasion on postoperative neurocognitive recovery in patients with low-grade glioma (LGG). MATERIALS AND METHODS We retrospectively analyzed LGG patients (WHO grade 2-3) who underwent surgical resection and remained in stable disease between 2017 and 2025. Neurocognitive function was assessed at five time points: preoperatively (baseline), and at <4.5 months, 4.5–10.5 months, 10.5–16.5 months, and >16.5 months postoperatively. Standardized domain-specific Z-scores were calculated, with scores < -1.5 classified as cognitive impairment. Group comparisons were performed using Mann–Whitney U tests and repeated-measures ANOVA. RESULTS Among 53 LGG patients, 25 had SVZ invasion (SVZ+) and 28 did not (SVZ-). At baseline, SVZ+ patients showed poorer performance across all cognitive domains except processing speed. Longitudinally, language and working memory transiently worsened but recovered in SVZ+ group within postoperative 1 year. Other domains of function remained stable comparing to baseline in both groups. Repeated-measures ANOVA revealed significantly poorer cognitive recovery trajectories in the SVZ+ group across most domains, including global cognition, auditory learning, visual learning, language, spatial perceptual, executive function, processing speed and working memory, excluding orientation and emotion. Multivariable logistic regression identified SVZ invasion (OR = 12.56, p = 0.018) and advanced age (OR = 1.12, p = 0.029) as independent predictors of cognitive impairment at 4.5–10.5 months. At 10.5–16.5 months, SVZ invasion (OR = 12.05, p = 0.050) and lower educational level (OR = 0.45, p = 0.022) remained significant predictors. CONCLUSION Transient decline of language and working memory function has been found in only SVZ-invaded group. SVZ involvement, older age, and lower education are independent risk factors for delayed cognitive recovery. These findings underscore the need for early detection of SVZ invasion and individualized neurocognitive monitoring in LGG management.