Department of Radiology, Division of Neuroradiology, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, NY.
Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, NewYork-Presbyterian Hospital, New York, NY.
J Neuroimaging. 2020 Nov;30(6):901-909. doi: 10.1111/jon.12763. Epub 2020 Jul 28.
Glioblastomas (GBMs) that involve the subventricular zone (SVZ) have a poor prognosis, possibly due to recruitment of neural stem cells. The purpose of this study was to evaluate whether SVZ involvement by lower grade gliomas (LGG), WHO grade II and III, similarly predicts poorer outcomes. We further assessed whether tumor genetics and cellularity are associated with SVZ involvement and outcomes.
Forty-five consecutive LGG patients with preoperative imaging and next generation sequencing were included in this study. Regional SVZ involvement and whole tumor apparent diffusion coefficient (ADC) values, as a measure of cellularity, were assessed on magnetic resonance imaging. Progression was determined by RANO criteria. Kaplan-Meier curves and Cox regression analyses were used to determine the hazard ratios (HR) for progression and survival.
Frontal, parietal, temporal, and overall SVZ involvement and ADC values were not associated with progression or survival (P ≥ .05). However, occipital SVZ involvement, seen in two patients, was associated with a higher risk of tumor progression (HR = 6.6, P = .016) and death (HR = 31.5, P = .015), CDKN2A/B mutations (P = .03), and lower ADC histogram values at the 5th (P = .026) and 10th percentiles (P = .046). Isocitrate dehydrogenase, phosphatase and tensin homolog, epidermal growth factor receptor, and cyclin-dependent kinase 4 mutations were also prognostic (P ≤ .05).
Unlike in GBM, overall SVZ involvement was not found to strongly predict poor prognosis in LGGs. However, occipital SVZ involvement, though uncommon, was prognostic and found to be associated with CDKN2A/B mutations and tumor hypercellularity. Further investigation into these molecular mechanisms underlying occipital SVZ involvement in larger cohorts is warranted.
涉及侧脑室下区（SVZ）的胶质母细胞瘤（GBM）预后较差，可能是由于招募了神经干细胞。本研究旨在评估低级别胶质瘤（LGG），即 WHO 分级 II 级和 III 级，SVZ 受累是否同样预示着较差的预后。我们进一步评估了肿瘤遗传学和细胞密度是否与 SVZ 受累和结果相关。
本研究纳入了 45 例连续的 LGG 患者，这些患者术前均进行了影像学和下一代测序检查。在磁共振成像上评估了局部 SVZ 受累情况和全肿瘤表观扩散系数（ADC）值，作为细胞密度的测量指标。采用 RANO 标准确定进展情况。采用 Kaplan-Meier 曲线和 Cox 回归分析确定进展和生存的风险比（HR）。
额部、顶叶、颞叶和整体 SVZ 受累以及 ADC 值与进展或生存无关（P≥.05）。然而，两名患者存在枕部 SVZ 受累，与肿瘤进展风险较高相关（HR=6.6，P=0.016）和死亡风险较高相关（HR=31.5，P=0.015），与 CDKN2A/B 突变相关（P=0.03），以及 5%和 10% ADC 直方图值较低相关（P=0.026 和 P=0.046）。异柠檬酸脱氢酶、磷酸酶和张力蛋白同源物、表皮生长因子受体和周期蛋白依赖性激酶 4 突变也具有预后意义（P≤.05）。
与 GBM 不同，在 LGG 中，整体 SVZ 受累并未强烈预测预后不良。然而，尽管枕部 SVZ 受累不常见，但具有预后意义，并且与 CDKN2A/B 突变和肿瘤高细胞密度相关。需要在更大的队列中进一步研究这些枕部 SVZ 受累的分子机制。
