Department of Radiology and Nuclear Medicine, Xuanwu Hospital, Capital Medical University, No.45 Changchun Street, Xicheng District, 100053, Beijing, People's Republic of China.
Department of Nuclear Medicine, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
Eur Radiol. 2022 Aug;32(8):5577-5587. doi: 10.1007/s00330-022-08606-9. Epub 2022 Feb 22.
To investigate the effects of O-methylguanine DNA methyltransferase (MGMT) promoter methylation status of gliomas on O-(2-F-fluoroethyl)-L-tyrosine ([F]FET) uptake and cerebral blood flow (CBF) of arterial spin labeling (ASL), evaluated by hybrid PET/MR. Stereotactic biopsy was used to validate the findings.
A set of whole tumor and reference volumes of interest (VOIs) based on PET/FLAIR imaging were delineated and transferred to the corresponding [F]FET PET and CBF maps in 57 patients with newly diagnosed gliomas. The mean and max tumor-to-brain ratio (TBR) and normalized CBF (nCBF) were calculated. The predictive efficacy of [F]FET PET and CBF in determining MGMT promoter methylation status of glioma were evaluated by whole tumor analysis and stereotactic biopsy. The correlation between PET/MR parameters and MGMT promoter methylation were analyzed using histological specimens acquired from multiple stereotactic biopsies.
Based on the analysis of whole tumor volume and biopsy site, TBRmean, TBRmax, nCBFmean, and nCBFmax showed no statistically significant differences between gliomas with and without MGMT promoter methylation (all p > 0.05). Furthermore, stereotactic biopsy demonstrated that TBRmean, TBRmax, nCBFmean, and nCBFmax showed no correlation with MGMT promoter methylation (r = -0.117, p = 0.579; r = -0.161, p = 0.443; r = -0.271, p = 0.191; r = -0.300, p = 0.145; respectively).
MGMT promoter methylation status shows no effect on [F]FET uptake and CBF of ASL in gliomas. Stereotactic biopsy validates it and further reveals there is no correlation of [F]FET PET uptake and CBF with the percentages of MGMT promoter methylation.
• Based on whole tumor VOI assessment, MGMT promoter methylation status shows no effect on [F]FET uptake and CBF of ASL in gliomas. • For WHO grade IV glioblastomas, [F]FET PET and ASL parameters based on hybrid PET/MR fail to predict the MGMT promoter methylation status. • Stereotactic image-based histology reveals that there is no correlation of [F]FET PET uptake and CBF with the status and percentages of MGMT promoter methylation in gliomas.
通过杂交 PET/MR 研究脑胶质瘤 O-甲基鸟嘌呤-DNA 甲基转移酶（MGMT）启动子甲基化状态对 O-（2-氟乙基）-L-酪氨酸（[F]FET）摄取和动脉自旋标记（ASL）脑血流（CBF）的影响。采用立体定向活检验证这一发现。
对 57 例新诊断脑胶质瘤患者的 PET/FLAIR 图像进行全肿瘤和参考感兴趣区（VOI）勾画，并将其转移至相应的[F]FET PET 和 CBF 图上。计算平均和最大肿瘤与脑比值（TBR）和归一化 CBF（nCBF）。通过全肿瘤分析和立体定向活检评估[F]FET PET 和 CBF 对脑胶质瘤 MGMT 启动子甲基化状态的预测效能。利用从多个立体定向活检中获得的组织学标本，分析 PET/MR 参数与 MGMT 启动子甲基化的相关性。
基于全肿瘤体积和活检部位分析，MGMT 启动子甲基化组与非甲基化组之间的 TBRmean、TBRmax、nCBFmean 和 nCBFmax 无统计学差异（均 P>0.05）。此外，立体定向活检显示 TBRmean、TBRmax、nCBFmean 和 nCBFmax 与 MGMT 启动子甲基化无相关性（r=-0.117，P=0.579；r=-0.161，P=0.443；r=-0.271，P=0.191；r=-0.300，P=0.145）。
MGMT 启动子甲基化状态对脑胶质瘤[F]FET 摄取和 ASL CBF 无影响。立体定向活检验证了这一点，并进一步表明[F]FET PET 摄取和 CBF 与 MGMT 启动子甲基化的百分比无相关性。
基于全肿瘤 VOI 评估，MGMT 启动子甲基化状态对脑胶质瘤[F]FET 摄取和 ASL CBF 无影响。
对于 WHO Ⅳ级脑胶质瘤，基于杂交 PET/MR 的[F]FET PET 和 ASL 参数不能预测 MGMT 启动子甲基化状态。
立体定向图像引导下的组织学研究显示，[F]FET PET 摄取和 CBF 与脑胶质瘤中 MGMT 启动子甲基化的状态和百分比无相关性。
