The Value Of Gadolinium-Ethoxybenzyl-Diethylenetriamine Pentaacetic Acid Enhanced MRI T1 Mapping For Assessing And Predicting Ki-67 Expression Of Hepatocellular Carcinoma

Objective:1.To explore the correlation between gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced MRI T1 mapping and Ki-67 expression in hepatocellular carcinoma.2.To explore the value of Gd-EOB-DTPA enhanced MRI T1 mapping nomogram model for preoperative prediction of Ki-67 expression in hepatocellular carcinoma.Materials and Methods:1.The data of 74 patients diagnosed with hepatocellular carcinoma in our hospital from July 2019 to December 2020 were retrospectively collected.Gd-EOB-DTPA enhanced MRI Tlmapping was performed before surgery,and Ki-67 immunohistochemistry was performed after surgery.Among them,65 were males and 9 were females,aged between 30 and 84 years old,with an average age of 59.69± 10.57 years old.Analyze the correlation between the quantitative parameters of Gd-EOB-DTPA enhanced MRI and pathological Ki-67 expression,and divide them into Ki-67 low expression group(≤25%,40 cases)and Ki-67 high expression group(>25%,34 cases),according to Ki-67 Label index.Spearman correlation analysis method was used to analyze the image quantitative parameters T1 relaxation time(Tlrt),reduction rate of T1 relaxation time(rrTlrt),Tumor to liver contrast ratio(TLR),contrast enhancement ratio(CER),ADC and Ki-67 correlation.Tumor to liver contrast ratio-portal phase(TLR-PP)and tumor to liver contrast ratio-equilibrium phase(TLR-EP)between the two groups are represented by Mediam(P25,P75)and Mann-Whitney U Test,the rest of the quantitative parameters are expressed in terms of independent sample t test.And according to the ROC curve,compare the area under the curve(AUC)of T1rt,Tlrt-20min,TLR-pre,TLR-HBP,ADC parameter values,sensitivity,specificity,Youden index,and critical value.2.Patient data collection,MRI examination,Ki-67 immunohistochemical staining,and Ki-67 labeling index grouping are the same as the first part.The two groups of clinical data(gender,hepatitis,liver cirrhosis,etc.)and imaging qualitative parameters(tumor edge,pseudo capsule,arterial phase ring enhancement,etc.)were compared using the χ2 test,and the imaging quantitative parameter analysis was roughly the same as the first part.Incorporate the above statistically significant parameters into multivariate logistic regression to obtain independent predictors of high Ki-67 expression in hepatocellular carcinoma and establish a nomogram model for predicting Ki-67 expression in hepatocellular carcinoma.Result:1.T1rt-Pre,T1rt-20min and Ki-67 are strongly positively correlated(r=0.668,r=0.659,P<0.001);TLR-pre,TLR-HBP and Ki-67 are moderately negatively correlated(r=-0.495,r=-0.497,P<0.001);ADC value was negatively correlated with Ki-67(r=-0.478,P<0.001);TLR-PP,TLR-EP was weakly negatively correlated with Ki-67(r=-0.272,P=0.019,r=-0.362,P=0.002).T1rt-Pre,Tlrt-20min,TLR-pre,TLR-AP,TLR-EP,TLR-HBP;ADC between the Ki67 high and low expression groups were all statistically significant(P<0,05).The area under the curve(AUC)values of Tlrt-Pre,Tlrt-20min,TLR-pre,TLR-HBP,and ADC were 0.868,0.890,0.717,0.782,0.747,respectively(p<0.001).Among them,Tlrt-20min has a high diagnostic efficiency(Youden=0.65),with a sensitivity of 85.3%and a specificity of 80.0%,The cut-off value is>724.5 msec.2.AFP,tumor margin,Arterial rim enhancement,mosaic architecture,corona enhancement and peritumor hypointensity were significantly different in the high and low Ki-67 expression groups(χ2 values were 17.185,25.395,8.061,5.868,11.777,6.613,P<0.05),the long diameter,Tlrt-Pre,Tlrt-20min,ADC,TLR-pre,TLR-AP,TLR-EP,TLR-HBP between groups are all statistically significant(z=-3.408,t=6.947,t=7.765,t=-4.616,t=-3.785,t=-2.186,z=-2.653,t=-4.560,all P<0.05).Multivariate logistic regression results showed that AFP≥20 μg/L,non-smooth tumor margins,and T1rt-20min>724.5 msec were independent predictors of Ki-67 high expression(odds ratios were 10.106,18.514,1.016,P<0.05).The nomogram model of Gd-EOB-DTPA enhanced MRI T1 mapping for predicting the expression of hepatocellular carcinoma Ki-67 before surgery was successfully established.The area under the receiver operating characteristic curve was 0.955.The calibration prediction curve and the standard curve fit well.Conclusions:1.Gd-EOB-DTPA enhanced MRI T1 mapping has a strong positive correlation with Ki-67 expression in hepatocellular carcinoma,and has a good ability to evaluate Ki-67 expression in hepatocellular carcinoma.2.Gd-EOB-DTPA enhanced MRI T1 mapping nomogram model has high application value in predicting Ki-67 expression before operation,and it provides an individualized prediction method for Ki-67 expression in hepatocellular carcinoma patients.