F-FET PET/CT影像学数据,根据病理学分级将患者分成低级别胶质瘤组[世界卫生组织(World Health Organization,WHO)Ⅱ级,共计32例]和高级别胶质瘤组(WHO Ⅲ级13例、WHO Ⅳ级13例,共计26例)。在PET、CT影像模态中分别提取105个影像组学特征参数进行分析,采用基于R语言机器学习算法的5折交叉验证最小绝对收缩与选择算子(least absolute shrinkage and selection operator,LASSO)回归分析方法,构建成人胶质瘤病理学分级的3个独立的影像组学预测模型(PET-Rad模型、CT-Rad模型和PET/CT-Rad模型),然后再采用全子集回归对影像组学预测模型进行校正。采用受试者工作特征曲线的曲线下面积(area under curve,AUC)对预测模型进行评价。
结果:
基于4个
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F-FET PET影像组学参数建立PET-Rad模型的AUC为0.845(95% CI 0.726~0.927);基于3个CT影像组学参数构建的CT-Rad模型的AUC为0.802(95% CI 0.676~0.895);而联合3个CT和2个PET影像组学特征的
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F-FET PET/CT-Rad模型的AUC为0.901(95% CI 0.794~0.964),准确度为86.21%。DeLong检验结果显示PET/CT-Rad模型优于CT-Rad模型(
and investigate the predictive efficacy for tumor grading in untreated adult gliomas.
Methods:
The
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F-FET PET/CT imaging data of 58 histopathologically confirmed untreated adult gliomas were retrospectively analyzed. Based on pathological grading
the patients were divided into low-grade glioma groups [World Health Organization (WHO) Grade Ⅱ
32 cases in total] and high-grade gliomas (13 cases for WHO grade Ⅲ
13 cases for WHO grade Ⅳ
26 cases in total). 105 radiomics features were extracted from PET and CT modalities respectively. Five-fold cross-validation least absolute shrinkage and selection operator (LASSO) regression analysis based on R-language machine learning algorithm and all- subset regression were adopted to filter and optimize the identify the optimal feature combinations with higher distinguishing power for glioma grading. Three independent radiomics prediction models (PET-Rad model
CT-Rad model and PET/CT-Rad model) for adult glioma pathological grading were constructed. The area under the receiver operating characteristic curve (AUC) was used to evaluate the prediction model.
Results:
The AUC of PET-Rad model based on four
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F-FET PET radiomics features was 0.845 (95% CI 0.726-0.927) and the AUC of CT-Rad model consisting of three CT radiomics features was 0.802 (95% CI 0.676-0.895). The AUC of the
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F-FET PET/ CT-Rad model combined with three CT and two PET radiomics features was 0.901 (95% CI 0.794-0.964)
and the accuracy was 86.21%. DeLong test results
showed that PET/CT-Rad model was superior to CT-Rad model (
P
=0.032). The efficacy of PET/CT-Rad model was better than that of PET-Rad model
but there was no statistical difference (
P
=0.146). The three CT imaging parameters in PET/CT-Rad model were firstorder_10Percentile
glrlm_LowGrayLevelRunEmphasis
and ngtdm_Busyness
while Glrlm_LowGrayLevelRunEmphasis was the most important predictive variable with a relative importance of 30.97%. The relative importance of the other two selected PET radiomic features firstorder_Maximum and ngtdm_Contrast was 21.99% and 21.01%
respectively.
Conclusion:
The non-invasive prediction model based on the combination of integrated
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F-FET PET and CT modality radiomic features can effectively help grading the untreated adult glioma
facilitating clinical decision-making for patients with varied glioma grades.