UCLA Brain Tumor Imaging Laboratory (BTIL), Center for Computer Vision and Imaging Biomarkers, University of California, Los Angeles, Los Angeles, California, USA.
Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
Neuro Oncol. 2022 Jun 1;24(6):1020-1028. doi: 10.1093/neuonc/noab276.
Diffusion MRI estimates of the apparent diffusion coefficient (ADC) have been shown to be useful in predicting treatment response in patients with glioblastoma (GBM), with ADC elevations indicating tumor cell death. We aimed to investigate whether the ADC values measured before and after treatment with immune checkpoint inhibitors (ICIs) and the changes in these ADC values could predict overall survival (OS) in patients with recurrent IDH wild-type GBM.
Forty-four patients who met the following inclusion criteria were included in this retrospective study: (i) diagnosed with recurrent IDH wild-type GBM and treated with either pembrolizumab or nivolumab and (ii) availability of diffusion data on pre- and post-ICI MRI. Tumor volume and the median relative ADC (rADC) with respect to the normal-appearing white matter within the enhancing tumor were calculated.
Median OS among all patients was 8.1 months (range, 1.0-22.5 months). Log-rank test revealed that higher post-treatment rADC was associated with a significantly longer OS (median, 10.3 months for rADC ≥ 1.63 versus 6.1 months for rADC < 1.63; P = .02), whereas tumor volume, pretreatment rADC, and changes in rADC after treatment were not significantly associated with OS. Cox regression analysis revealed that post-treatment rADC significantly influenced OS (P = .02, univariate analysis), even after controlling for age and sex (P =.01, multivariate analysis), and additionally controlling for surgery after ICI treatment (P = .045, multivariate analysis).
Elevated post-treatment rADC may be an early imaging biomarker for OS benefits in GBM patients receiving ICI treatment.
扩散 MRI 估计的表观扩散系数 (ADC) 已被证明可用于预测胶质母细胞瘤 (GBM) 患者的治疗反应，ADC 升高表明肿瘤细胞死亡。我们旨在研究接受免疫检查点抑制剂 (ICI) 治疗前后测量的 ADC 值以及这些 ADC 值的变化是否可以预测复发性 IDH 野生型 GBM 患者的总生存期 (OS)。
本回顾性研究纳入了符合以下纳入标准的 44 名患者：(i) 诊断为复发性 IDH 野生型 GBM 并接受 pembrolizumab 或 nivolumab 治疗，以及 (ii) 具有 ICI MRI 治疗前后扩散数据。计算肿瘤体积和相对于增强肿瘤内正常外观白质的中位数相对 ADC (rADC)。
所有患者的中位 OS 为 8.1 个月（范围，1.0-22.5 个月）。对数秩检验显示，较高的 post-treatment rADC 与更长的 OS 显著相关（rADC ≥ 1.63 的中位 OS 为 10.3 个月，rADC < 1.63 的中位 OS 为 6.1 个月；P =.02），而肿瘤体积、预处理 rADC 和治疗后 rADC 的变化与 OS 无显著相关性。Cox 回归分析显示，post-treatment rADC 显著影响 OS（P =.02，单因素分析），甚至在控制年龄和性别后（P =.01，多因素分析），并在控制 ICI 治疗后的手术后进一步控制（P =.045，多因素分析）。
升高的 post-treatment rADC 可能是接受 ICI 治疗的 GBM 患者 OS 获益的早期影像学生物标志物。
