Department of Electronic Engineering, Fudan University, Shanghai, 200433, China.
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Int J Comput Assist Radiol Surg. 2020 Jun;15(6):921-930. doi: 10.1007/s11548-020-02177-0. Epub 2020 May 9.
A highly accurate and robust computer-aided system based on quantitative high-throughput Breast Imaging Reporting and Data System (BI-RADS) features from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can drive the success of radiomic applications in breast cancer diagnosis. We aim to build a stable system with highly reproducible radiomics features, which can make diagnostic performance independent of datasets bias and segmentation methods.
We applied a dataset of 267 patients including 136 malignant and 131 benign tumors from two MRI manufacturers, where 211 cases from a Philips system and 55 cases from a GE system. First, manual annotations, 3D-Unet and 2D-Unet were applied as different segmentation methods. Second, we designed and extracted 3172 features from six modalities of DCE-MRI based on BI-RADS. Third, the feature selection was conducted. Between-class distance was utilized to eliminate the effect of dataset bias caused by two machines. Concordance correlation coefficient, intraclass correlation coefficient and deviation were employed to evaluate the influence of three segmentation methods. We further eliminated features redundancy using genetic algorithm. Finally, three classifiers including support vector machine (SVM), the bagged trees and K-Nearest Neighbor were evaluated by their performance for diagnosing malignant and benign tumors.
A total of 246 features were preserved to have high stability and reproducibility. The final feature set showed the robust performance under these factors and achieved the area under curve of 0.88, the accuracy of 0.824, the sensitivity of 0.844, the specificity of 0.807 in differentiating benign and malignant tumors with the SVM classifier using manually segmentation results.
The final selected 246 features are reproducible and show little dependence on segmentation methods and data perturbation. The high stability and effectiveness of diagnosis across these factors illustrate that the preserved features can be used for prognostic analysis and help radiologists in the diagnosis of breast cancer.
基于动态对比增强磁共振成像(DCE-MRI)的定量高通量乳腺影像报告和数据系统(BI-RADS)特征,建立一个高度准确和稳健的计算机辅助系统,可以推动放射组学在乳腺癌诊断中的成功应用。我们的目标是建立一个具有高度可重复性的放射组学特征的稳定系统,使诊断性能不受数据集偏差和分割方法的影响。
我们应用了来自两个 MRI 制造商的 267 例患者的数据集,其中包括 136 例恶性肿瘤和 131 例良性肿瘤,其中 211 例来自飞利浦系统,55 例来自通用电气系统。首先,采用手动注释、3D-Unet 和 2D-Unet 作为不同的分割方法。其次,我们根据 BI-RADS 从 DCE-MRI 的六种模式中设计并提取了 3172 个特征。然后进行特征选择。使用类间距离消除了两种机器引起的数据集偏差的影响。采用一致性相关系数、组内相关系数和偏差来评估三种分割方法的影响。我们进一步使用遗传算法消除特征冗余。最后,使用支持向量机(SVM)、袋装树和 K-最近邻三种分类器来评估其诊断良恶性肿瘤的性能。
共有 246 个特征被保留下来,具有较高的稳定性和可重复性。最终的特征集在这些因素下表现出稳健的性能,使用手动分割结果,SVM 分类器在区分良恶性肿瘤时的曲线下面积为 0.88,准确率为 0.824,灵敏度为 0.844,特异性为 0.807。
最终选择的 246 个特征具有可重复性,对分割方法和数据干扰的依赖性较小。这些因素下的高稳定性和诊断效果表明,保留的特征可用于预后分析,并有助于放射科医生进行乳腺癌诊断。