Radiomic Analysis of Contrast-Enhanced MRI Predicts DNA Copy-Number Subtype and Outcome in Lower-Grade Gliomas

DNA copy-number (CN)2-subtype impairs outcomes in patients with lower-grade gliomas (LGG). We aimed to determine the value of preoperative nomograms integrating radiomic and radiographic (RR) features in predicting DNA copy-number subtype.Data of 153 consecutive patients were retrospectively analyzed. A total of 1167 radiomics features were extracted from contrast-enhanced MR images. LASSO logistic regression was performed to choose the key features and construct a radiomics signature. Three CN-related RR model were built with multivariate logistic regression.CN2-subtype was associated with shortest median PFS(p <0.001) and OS (p <0.001). The radiomics nomogram, which incorporated the signature (AUC:0.891, OR: 2.345; p = 0.001), extranodular growth (OR: 14.413; p <0.001) and width (OR: 0.194; p = 0.027), distinguished CN2-subtype with an AUC of 0.924(95%CI: 0.869-0.979).The radiomics nomogram, which incorporated the signature (AUC:0.730, OR: 2.408; p = 0.001), hemorrhage (OR: 0.100; p <0.001), poorly-defined margin (OR:4.433; p = 0.001) and volume>=60cm3 (OR: 4.195; p = 0.002) were associated with CN1-subtype (AUC:0.829,95%CI:0.765-0.892).The radiomics nomogram, which incorporated the signature (AUC:0.660, OR: 2.518; p = 0.003), necrosis/cystic(OR:6.975; p = 0.008), hemorrhage (OR:3.723; p = 0.024), poorly-defined margin (OR:0.124; p <0.001) and frontal lobe tumors (OR: 4.870; p <0.001) were associated with CN3-subtype (AUC: 0.837,95%CI: 0.767-0.909).All three RR models showed good discrimination and calibration. Decision curve analysis indicated that all RR models were clinically useful. The average accuracy of the ten-fold cross validation was 92.8% for CN2-subtype, 72.6% for CN1-subtype and 79.0% for CN3-subtype.The shortest PFS and OS was observed in LGG patients with CN2-subtype. The RR models, integrating radiomic and radiographic features, demonstrates good performance for predicting DNA copy-number subtype and clinical outcomes.