Predictive Value Of Gd-EOB-DTPA Enhanced MRI And ADC Values For Microvascular Invasion In Isolated Hepatocellular Carcinoma

Objective:To investigate the image features of Gd-EOB-DTPA enhanced magnetic resonance imaging（MRI）and to predict the microvascular invasion of（MVI）in the diagnosis of isolated hepatocellular carcinoma（HCC）by using its apparent diffusion coefficient（Apparent diffusion coefficient,ADC）.Methods:The preoperative MRI data of 86 patients with hepatocellular carcinoma confirmed by operation and pathology in a medical imaging center of a hospital from March 2017 to January 2020 were analyzed retrospectively.3.0T MRI plain scan,enhanced DWI and imaging scan were performed in all patients before operation,and the imaging data were analyzed,including tumor diameter,steatosis,peritumor enhancement in arterial phase,low signal intensity in hepatobiliary phase,tumor pseudocapsule,smooth tumor margin,tumor relative enhancement RE（relativeenhancement,RE）,mean and minimum ADC,and general clinical data of patients including preoperative alpha-fetoprotein（α-fetoprotein AFP）.Age,sex,presence or absence of liver cirrhosis,and tumor pathological Edmondson-Steiner grade were used to evaluate the correlation with microvascular invasion of hepatocellular carcinoma（HCC）.According to the pathological results,the cases were divided into MVI negative group（M-）and MVI positive group（M+）.Pearson’s chi-square test was used to analyze the counting data between the two groups,independent sample t-test（normal distribution）and Mann-Whitney U test（skewness distribution）were used to analyze the metrological data between the two groups.The joint probability of multiple factors is calculated by binary Logstic regression model,and the ROC curve of single factor and multiple factors for predicting MVI is drawn.Results:（1）In terms of image morphological features,the low signal around hepatobiliary tumor,the irregular edge of hepatobiliary tumor,and the tumor diameter equal to or larger than 3.8cm were significantly different between the two groups with or without MVI.The sensitivity and specificity for the diagnosis of MVI were 90.00%、75.76%,95.00%、50.00%,49.23%,respectively.The Youden index was 0.6576,0.4500 and 0.3923 respectively,and the area under the receiver operating characteristic（ROC）curve was 0.827,0.721 and 0.725,respectively.When the three signs combined to predict MVI,the area under the ROC curve was 0.89,but there was no significant difference between the two groups with or without peri-tumor enhancement,steatosis and tumor pseudocapsule in arterial phase（P>0.05）.（2）the average ADC value and the minimum ADC value were significantly different between the two groups with or without MVI.The average ADC value of 1.079×10^-3mm²/s was the best critical value,the area under the ROC curve was 0.747,the sensitivity was 85.00%,the specificity was 59.09%,and the Youden index was 0.4258;The minimum ADC value of 0.785×10^-3mm²/s was the best critical value,the area under the ROC curve was 0.772,the sensitivity was 75.00%,the specificity was 74.24%,and the Youden index was 0.4924,while there was no significant difference in relative enhancement on arterial phase（AP-RE）.（3）in terms of general clinical data,there was significant difference in alpha-fetoprotein between groups with and without MVI.The best critical value was 27.45ng/ml,AUC was 0.736,and the sensitivity and specificity were 80.00%and 66.67%,respectively.Youden index was 0.4667.When AFP combined with low signal intensity around hepatobiliary tumor,irregular margin of hepatobiliary tumor and tumor diameter equal to or greater than 3.8cm to predict MVI,AUC was 0.902,but there was no significant difference in sex,age and history of liver cirrhosis between patients with and without MVI（P>0.05）.Conclusion:（1）The morphological features of Gd-EOB-DTPA enhanced MR images show that there are statistically significant differences between the two groups in the presence or absence of MVI,such as low signal around hepatobiliary tumor,incomplete margin of hepatobiliary tumor,and tumor diameter equal to or greater than 3.8cm,which is of certain value for predicting MVI.Among the morphological indexes,low signal around hepatobiliary tumor has the highest accuracy for predicting MVI,and is higher than the average ADC value and minimum ADC value of quantitative indexes.（2）In quantitative indicators,the difference between the average ADC value and the minimum ADC value with or without MVI is statistically significant,and to a certain extent,both can predict MVI,but the difference between the two has no significant statistical significance for predicting MVI.（3）In general clinical data,the difference of AFP high expression between the two groups with and without MVI is statistically different,which has medium accuracy for predicting MVI.When AFP combined with gadolinium disodium citrate enhances MR image morphological characteristics,it has high accuracy for predicting MVI.