基于T1 mapping技术的定量参数评估肝细胞肝癌微血管侵犯的研究

Research on evaluation of microvascular invasion in hepatocellular carcinoma based on quantitative parameters of T1 mapping

目的:探讨基于T1 mapping技术的定量参数在预测肝细胞肝癌(hepatocellular carcinoma,HCC)微血管侵犯(microvascular invasion,MVI)的价值。方法:回顾性分析34例接受肝脏特异性对比剂钆塞酸二钠(Gd-EOB-DTPA)增强MRI检查且术后病理及免疫组化证实为HCC患者的临床及磁共振影像资料,根据MVI状态分为MVI阳性组(21例)及MVI阴性组(13例)。所有患者均行平扫期及平衡期的T1 mapping成像,测量肿瘤实质部分、肿瘤整体、瘤周1 cm以及正常肝实质背景的T1弛豫时间,结合红细胞压积水平,计算肿瘤实质及肿瘤整体的细胞外容积分数(ECV)。比较MVI两组之间各T1弛豫时间及ECV定量参数之间的差异,采用受试者工作特征(receiver operating characteristic,ROC)曲线评价各变量的诊断效能,并计算截断值、敏感度、特异度及曲线下面积(area under curve,AUC)。结果:MVI阳性组与MVI阴性组间在瘤周1 cm增强前T1弛豫时间、肿瘤实质ECV和肿瘤整体ECV上差异有统计学意义(P<0.05),AUC分别为0.707(95%CI:0.509~0.905)、0.780(95%CI:0.593~0.967)和0.736(95%CI:0.5469~0.9256)。结论:基于T1 mapping技术的瘤周1 cm增强前T1弛豫时间、肿瘤实质ECV及肿瘤整体ECV均可反映HCC患者的MVI状态,临床应用具有一定的可行性。

Objective:To investigate the value of quantitative parameters based on T1 mapping technology in predicting microvascular invasion(MVI)in hepatocellular carcinoma(HCC).Methods:The clinical and magnetic resonance imaging data of 34 patients receiving liver-specific contrast diodium gadololite(Gd-EOB-DTPA)-enhanced MRI with postoperative pathology and immunohistochemistry were retrospectively analyzed.According to the MVI status,they were divided into MVI positive group(21 cases)and MVI negative group(13 cases).All patients underwent T1 mapping imaging during the plain scanning phase and the equilibrium phase,T1 relaxation time of the tumor parenchymal part,tumor bulk,1 cm around the tumor and normal liver parenchymal background were measured.The extracellular volume fraction(ECV)of the tumor parenchyma and the overall tumor was calculated,combined with the hematocrit level.The differences in T1 relaxation time and the ECV quantitative parameters between the two MVI groups were compared.The diagnostic efficacy of each variable was evaluated using the receiver operating characteristic(ROC)curve,and the cut off value,sensitivity,specificity,and area under the curve(AUC)were calculated.Results:There were significant differences in T1 relaxation time before enhancement at 1 cm around the tumor,ECV of tumor parenchyma and overall tumor between MVI positive group and MVI negative group(P<0.05),with AUC 0.707(95%CI:0.509~0.905),0.0780(95%CI:0.593~0.967)and 0.736(95%CI:0.5469~0.9256).Conclusion:The T1 relaxation time,tumor parenchymal ECV and overall tumor ECV based on T1 mapping technology can reflect the MVI status of HCC patients,with clinical feasibility.