Thibault Guillaume, Tudorica Alina, Afzal Aneela, Chui Stephen Y-C, Naik Arpana, Troxell Megan L, Kemmer Kathleen A, Oh Karen Y, Roy Nicole, Jafarian Neda, Holtorf Megan L, Huang Wei, Song Xubo
Center Spatial Systems Biomedicine, BME, Oregon Health & Science University, Portland, Oregon.
Department of Diagnostic Radiology, Oregon Health & Science University, Portland, Oregon.
Tomography. 2017 Mar;3(1):23-32. doi: 10.18383/j.tom.2016.00241.
This study investigates the effectiveness of hundreds of texture features extracted from voxel-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parametric maps for early prediction of breast cancer response to neoadjuvant chemotherapy (NAC). In total, 38 patients with breast cancer underwent DCE-MRI before (baseline) and after the first of the 6-8 NAC cycles. Quantitative pharmacokinetic (PK) parameters and semiquantitative metrics were estimated from DCE-MRI time-course data. The residual cancer burden (RCB) index value was computed based on pathological analysis of surgical specimens after NAC completion. In total, 1043 texture features were extracted from each of the 13 parametric maps of quantitative PK or semiquantitative metric, and their capabilities for early prediction of RCB were examined by correlating feature changes between the 2 MRI studies with RCB. There were 1069 pairs of feature-map combinations that showed effectiveness for response prediction with 4 correlation coefficients >0.7. The 3-dimensional gray-level cooccurrence matrix was the most effective feature extraction method for therapy response prediction, and, in general, the statistical features describing texture heterogeneity were the most effective features. Quantitative PK parameters, particularly those estimated with the shutter-speed model, were more likely to generate effective features for prediction response compared with the semiquantitative metrics. The best feature-map pair could predict pathologic complete response with 100% sensitivity and 100% specificity using our cohort. In conclusion, breast tumor heterogeneity in microvasculature as measured by texture features of voxel-based DCE-MRI parametric maps could be a useful biomarker for early prediction of NAC response.
本研究调查了从基于体素的动态对比增强磁共振成像(DCE-MRI)参数图中提取的数百种纹理特征对乳腺癌新辅助化疗(NAC)反应进行早期预测的有效性。共有38例乳腺癌患者在6-8个NAC周期的第一个周期之前(基线)和之后接受了DCE-MRI检查。从DCE-MRI时间历程数据中估计了定量药代动力学(PK)参数和半定量指标。在NAC完成后,根据手术标本的病理分析计算残余癌负担(RCB)指数值。从定量PK或半定量指标的13个参数图中的每一个中总共提取了1043种纹理特征,并通过将两次MRI研究之间的特征变化与RCB相关联来检验它们对RCB早期预测的能力。有1069对特征-图组合显示出对反应预测有效,相关系数>0.7。三维灰度共生矩阵是治疗反应预测最有效的特征提取方法,一般来说,描述纹理异质性的统计特征是最有效的特征。与半定量指标相比,定量PK参数,特别是用快门速度模型估计的参数,更有可能产生用于预测反应的有效特征。使用我们的队列,最佳特征-图对可以以100%的敏感性和100%的特异性预测病理完全缓解。总之,基于体素的DCE-MRI参数图的纹理特征所测量的乳腺肿瘤微血管异质性可能是早期预测NAC反应的有用生物标志物。