Liu Qi, Zhang Jinggang, Jiang Man, Zhang Yue, Chen Tongbing, Zhang Jilei, Li Bei, Chen Jie, Xing Wei
Department of Radiology, The Third Affiliated Hospital of Soochow University, Changzhou, China.
Department of Hepatobiliary and Pancreatic Surgery, The Third Affiliated Hospital of Soochow University, Changzhou, China.
Front Oncol. 2021 Jun 23;11:670085. doi: 10.3389/fonc.2021.670085. eCollection 2021.
To explore the differences between intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and diffusion-weighted imaging (DWI) in evaluating the histopathological characters of pancreatic ductal adenocarcinoma (PDAC).
This retrospective study enrolled 50 patients with PDAC confirmed by pathology from December 2018 to May 2020. All patients underwent DWI and IVIM-DWI before surgeries. Patients were classified into low- and high-fibrosis groups. Apparent diffusion coefficient (ADC), diffusion coefficient (D), false diffusion coefficient (D*), and perfusion fraction (f) were measured by two radiologists, respectively in GE AW 4.7 post-processing station, wherein ADC values were derived by mono-exponential fits and f, D, D* values were derived by biexponential fits. The tumor tissue was stained with Sirius red, CD34, and CK19 to evaluate fibrosis, microvascular density (MVD), and tumor cell density. Furthermore, the correlation between ADC, D, D*, and f values and histopathological results was analyzed.
The D values were lower in the high-fibrosis group than in the low-fibrosis group, while the f values were opposite. Further, no statistically significant differences were detected in ADC and D* values between the high- and low-fibrosis groups. The AUC of D and f values had higher evaluation efficacy in the high- and low-fibrosis groups than ADC values. A significant negative correlation was established between D values, and fibrosis and a significant positive correlation were observed between f values and fibrosis. No statistical difference was detected between DWI/IVIM parameters values and MVD or tumor cell density except for the positive correlation between D* values and tumor cell density.
D and f values derived from the IVIM model had higher sensitivity and diagnostic performance for grading fibrosis in PDAC compared to the conventional DWI model. IVIM-DWI may have the potential as an imaging biomarker for predicting the fibrosis grade of PDAC.
探讨体素内不相干运动扩散加权成像（IVIM-DWI）与扩散加权成像（DWI）在评估胰腺导管腺癌（PDAC）组织病理学特征方面的差异。
本回顾性研究纳入了2018年12月至2020年5月间经病理确诊的50例PDAC患者。所有患者在手术前均接受了DWI和IVIM-DWI检查。患者被分为低纤维化组和高纤维化组。由两名放射科医生分别在GE AW 4.7后处理工作站测量表观扩散系数（ADC）、扩散系数（D）、伪扩散系数（D*）和灌注分数（f），其中ADC值通过单指数拟合得出，f、D、D值通过双指数拟合得出。肿瘤组织用天狼星红、CD34和CK19染色，以评估纤维化、微血管密度（MVD）和肿瘤细胞密度。此外，分析了ADC、D、D和f值与组织病理学结果之间的相关性。
高纤维化组的D值低于低纤维化组，而f值则相反。此外，高、低纤维化组之间的ADC和D值未检测到统计学显著差异。D和f值的AUC在高、低纤维化组中的评估效能高于ADC值。D值与纤维化之间建立了显著的负相关，f值与纤维化之间观察到显著的正相关。除D值与肿瘤细胞密度呈正相关外，DWI/IVIM参数值与MVD或肿瘤细胞密度之间未检测到统计学差异。
与传统DWI模型相比，IVIM模型得出的D和f值对PDAC纤维化分级具有更高的敏感性和诊断性能。IVIM-DWI可能有潜力作为预测PDAC纤维化分级的成像生物标志物。
