The Application Research Of Dynamic Contrast Enhanced MRI In Diagnosis Of Primary Liver Cancer

Objective:To investigate the value of dynamic contrast enhanced MRI(DCE-MRI) in diagnosis of primary liver cancer(PLC) and the correlation between perfusion parameters and pathological results, including the pathological grade, microvascular density (MVD) and vascular endothelial growth factor (VEGF) by contrastive analyzing the results of pathology and the results of DCE-MRI.Methods:From December,2012 to February,2016,sixty-three patients with liver lumps were examined by DCE-MRI and were verified by pathological findings. There were fifty-five men and eight womem in those patients. Their age were from twenty-five to sixty-eight and average age was 48.560±9.479 years old. After the exam, images were sent to the post-processing workstation of Siemens and measured by Tofts model,two-compartment model of Tissue-4D software. When drawing the outline of region of interest, the vascular area and necrosis area should be avoided. The perfusion parameters including the transfer constant (Ktrans), the volume of extravascular extracellular space per unit volume of tissue (Ve) and the rate constant (Kep) were calculated three times. The average values of parameters among the three times were the lesion parameters. Three normal liver tissues of the same level were selected as reference groups, which average values of parameters were the reference parameters. The relative parameters were the ratio of lesion parameters/ reference parameters. The parameters of precancerous lesions and parameters of the PLC were tested for differences. The parameters were contrastive analyzed respectively with pathological grade, MVD and VEGF. Statistic analyses were completed by using SPSS 16.0.Results:1.Histological resultsThere were 12 cases of precancerous lesions and 51 cases of PLC in the 63 patients. Among the 51 cases of PLC,10 ones were high differentiated,34 ones were middle differentiated and 7 ones were low differentiated.22 ones’ VEGF expressed negative(-),25 ones’VEGF expressed low level(+),4 ones’ VEGF expressed middle level(++) and no one expressed high level(+++).The patients’MVD marked by CD34 were in the range of 10 and 100.2.The differences between parameters of precancerous lesions and parameters of the PLC2.1. In the two groups, the difference of lesion Ktrans and relative Ktrans had statistical significance. The value of t were 3.851,3.837 respectively. The value of P were 0.000,0.000 respectively. When lesion Ktrans was 0.294 (min-1),the sensitivity of the diagnosis of PLC was 0.922 and the specificity was 0.750. When relative Ktrans was 2.064,the sensitivity of the diagnosis of PLC was 0.745 and the specificity was 1.000.2.2. In the two groups, the difference of lesion Ve and relative Ve had statistical significance. The value of t were 3.755,5.613 respectively. The value of P were 0.001,0.000 respectively. When lesion Ve was 0.427,the sensitivity of the diagnosis of PLC was 0.471 and the specificity was 1.000. When relative Ve was 4.277,the sensitivity of the diagnosis of PLC was 0.882 and the specificity was 0.917.2.3. In the two groups, the difference of lesion Kep and relative Kep had no statistical significance. The value of t were 1.419,-1.377 respectively. The value of P were 0.161,0.174 respectively.3. The correlation between perfusion parameters and the pathological gradeThe lesion Ktrans,lesion Kep,lesion Ve and relative Ktrans,relative Kep,relative Ve had no correlation with the pathological grade. The value of r were 0.158,0.080,0.117,0.126,0.221,-0.133 respectively and the value of P were 0.269,0.576,0.414,0.380,0.119,0.351 respectively. The values of lesion Ktrans, lesion Kep, relative Ktrans and relative Kep of middle differentiated PLC were biggest.4. The correlation between perfusion parameters and MVDThe lesion Ktrans had a positive correlation with MVD, r=0.533, P=0.000. The lesion Kep had no correlation with MVD, r=0.219, P=0.123. The lesion Ve had no correlation with MVD, has no correlation with MVD, r=0.150, P=0.295.The relative Ktrans had a positive correlation with MVD, r=0.791, P=0.000. The relative Kep had a positive correlation with MVD, r=0.717, P=0.000. The relative Ve had no correlation with MVD, r=-0.155, P=0.278.5. The correlation between perfusion parameters and VEGFThe lesion Ktrans,lesion Kep and lesion Ve had no correlation with VEGF.The value of r were 0.023,0.016,0.066 respectively.The value of P were 0.874,0.911,0.644 respectively.The relative Ktrans and the relative Kep had positive correlation with VEGF.The value of r were 0.398,0.379 respectively.The value of P were 0.004,0.006 respectively.Conclusions:DCE-MRI could reflect the microcirculation function of PLC. The perfusion parameters of DCE-MRI have great reference value not only in identifying the precancerous lesion and PLC but also in evaluating pathological characteristics.