^(18)F-FDG PET/CT图像的影像组学分析在胶质瘤MGMT基因甲基化状态评估中的初步应用

Radiomic analysis of ^(18)F-FDG PET/CT images in the evaluation of the MGMT methylation status in gliomas

目的探讨^(18)F-氟脱氧葡萄糖(FDG)PET/CT图像的影像组学分析综合评估O6-甲基鸟嘌呤-DNA甲基转移酶(MGMT)基因甲基化状态,预测胶质瘤患者对替莫唑胺(TMZ)治疗的反应。方法回顾性分析2016年1月至2018年9月在中国人民解放军总医院第一医学中心经组织病理学结果证实的17例胶质瘤患者,其中男性13例、女性4例,患者均于术前进行了^(18)F-FDG PET/CT检查,手动勾画肿瘤的感兴趣体积(VOI)并进行纹理分析。通过焦磷酸测序法检测、分析MGMT基因甲基化状态。根据MGMT基因甲基化状态分将患者为甲基化组和未甲基化组,采用两独立样本t检验分析两组数据之间各个影像组学参数的差异。结果17例胶质瘤患者中,9例(52.9%)MGMT基因未甲基化、8例(47.1%)MGMT基因甲基化。甲基化组与未甲基化组比较,患者的年龄和肿瘤分级的差异无统计学意义(t=-0.251、-0.016,P=0.806、0.198);而性别之间的差异有统计学意义(t=-1.426,P=0.031)。MGMT基因甲基化组的最大标准化摄取值(SUVmax)、最大肿瘤与正常组织摄取率(TNRmax)显著高于MGMT基因未甲基化组(SUVmax:18.83±7.77对9.66±4.13,t=-3.095,P=0.007;TNRmax:2.3740.87对1.20±0.52,t=-3.402,P=0.004)。结论^(18)F-FDG PET/CT图像的SUVmax和TNRmax可能是评估胶质瘤MGMT基因甲基化状态的关键指标,或许可用于预测TMZ化疗患者的临床反应。

Objective To explore the relationship between comprehensive information of gliomas and O6-methylguanylmethyltransferase(MGMT)promoter methylation status non-invasively by analyzing radiomic features of multi-modality ^(18)F-fluorodeoxyglucose(FDG)PET/CT images.The response to temozolomide(TMZ)was determined through the abovementioned method for the clinical management of glioma patients.Methods A retrospective study of 17 patients(13 males and 4 females)with glioma confirmed by histopathological results in the First Medical Center of General Hospital of Chinese PLA from January 2016 to September 2018 was conducted.Preoperative ^(18)F-FDG PET/CT scanning was performed.Radiomic texture analysis was performed after manually delineating the volume of interest.MGMT promoter methylation was examined by pyrosequencing analysis.MGMT data were categorized according to the methylation status,i.e.,methylated and unmethylated groups.Two independent sample t-tests were used to analyze the differences in imaging omics parameters between the two groups of data.Results Among the 17 patients with glioma,9(52.9%)had MGMT unmethylation and 8(47.1%)had MGMT methylation.Between the methylated group and the unmethylated group,there was no significant difference in patient age or tumor grade(t=-0.251,-0.016,P=0.806,0.198);The difference between genders was statistically significant Meaning(t=-1.426,P=0.031).Both the SUVmax and TNRmax values of the MGMT methylated group were significantly higher than those of the MGMT unmethylated group(SUVmax:18.83±7.77 VS.9.66±4.13;t=-3.095,P=0.007;TNRmax:2.37±0.87 vs.1.20±0.52;t=3.402,P=0.004).Conclusion The features(SUVmax and TNRmax)of ^(18)F-FDG PET/CT images are two key indicators in the detection of MGMT methylation status in gliomas and are valuable predictors of the clinical responses of patients scheduled to receive TMZ chemotherapeutics.