Diffusion radiomics analysis of intratumoral heterogeneity in a murine prostate cancer model following radiotherapy: Pixelwise correlation with histology
Diffusion radiomics analysis of intratumoral heterogeneity in a murine prostate cancer model following radiotherapy: Pixelwise correlation with histology
复制标题
DOI：
10.1002/jmri.25583
复制
发表时间：
2017-08-01
影响因子：
4.4
通讯作者：
Wang, Chun-Chieh
中科院分区：
文献类型：
--
作者：
Lin, Yu-Chun;Lin, Gigin;Wang, Chun-Chieh
目的探讨放射治疗后肿瘤表观扩散系数（ADC）值的生物学意义。第6天，在7 T下采集弥散加权图像，使用0至3000 s/mm（2）的多个b值。通过两点估计和信号衰减的单指数拟合计算的ADC值在肿瘤的照射和非照射区域之间进行比较。Pixelwise ADC地图与组织学指标，包括核计数，核大小，核空间，胞质空间，和细胞外spaces.ResultsAs相比，nonradiated区域，照射区域表现出ADC，细胞外空间，核大小的显着增加，核计数显着下降（P < 0.001）。通过两点法和单指数曲线拟合，在b值为800 s/mm（2）时获得了区分辐照区和非辐照区的最佳ADC。ADC值与细胞外间隙（r=0.74）、细胞核大小（r=0.72）呈正相关，与细胞核计数呈负相关（r=-0.82，P均< 0.001）。证据等级：1技术有效性：第2阶段J. MAGN. RESON。影像2017;46：483-489
PurposeTo investigate the biological meaning of apparent diffusion coefficient (ADC) values in tumors following radiotherapy.Materials and MethodsFive mice bearing TRAMP-C1 tumor were half-irradiated with a dose of 15 Gy. Diffusion-weighted images, using multiple b-values from 0 to 3000 s/mm(2), were acquired at 7T on day 6. ADC values calculated by a two-point estimate and monoexponential fitting of signal decay were compared between the irradiated and nonirradiated regions of the tumor. Pixelwise ADC maps were correlated with histological metrics including nuclear counts, nuclear sizes, nuclear spaces, cytoplasmic spaces, and extracellular spaces.ResultsAs compared with the nonirradiated region, the irradiated region exhibited significant increases in ADC, extracellular space, and nuclear size, and a significant decrease in nuclear counts (P < 0.001 for all). Optimal ADC to differentiate the irradiated from nonirradiated regions was achieved at a b-value of 800 s/mm(2) by the two-point method and monoexponential curve fitting. ADC positively correlated with extracellular spaces (r=0.74) and nuclear sizes (r=0.72), and negatively correlated with nuclear counts (r=-0.82, P < 0.001 for all).ConclusionAs a radiomic biomarker, ADC maps correlating with histological metrics pixelwise could be a means of evaluating tumor heterogeneity and responses to radiotherapy. Level of Evidence: 1 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:483-489