The Value Of Dynamic Contrast-Enhanced MRI Parameters Of Extended Tofts And Exchange Model In The Differential Diagnosis Of Hepatocellular Carcinoma And Hepatic Metastases

Objective:To analyze the value of dynamic contrast-enhanced MRI(DCE-MRI)parameters of Extended Tofts and Exchange Model in the differential diagnosis of Hepatocellular carcinoma(HCC)and Hepatic metastases of colorectal cancer.Materials and Methods:A retrospective analysis of 40 pathologically confirmed cases was conducted,including 25 cases of HCC and 15 cases of Hepatic metastases of colorectal cancer;all cases were underwent DCE-MRI.Applying liver double blood supplement model,and respectively using Extended Tofts two-compartment model and Exchange model calculated liver microvascular permeability parameters(Ktrans,Kep,Ve,and Vp)and the perfusion parameter HPI in the lesion parenchyma of HCC and metastases.We used t-test to compare the differences of the parameters measured from the two tumors,statistically significant parameters between HCC and metastases were screened which compared with the gold standard of pathological findings in order to draw the ROC curves to evaluate the diagnostic efficacy of different model parameters,using χ2 test compared the diagnostic accuracy of optimal parameters between the two models.Results:By using Extended Tofts and Exchange model,Ktrans value of HCC were respectively(0.661±0.402),(0.604±0.316)/min,Ktrans value of Hepatic metastases were respectively(0.196±0.175),(0.179±0.135)/min;Vp value of HCC were(0.334±0.217),(0.294±0.098),Vp value of Hepatic metastases were(0.089±0.015),(0.0891±0.022),respectively;HPI value of HCC were(0.680±0.281),(0.769±0.245),HPI value of Hepatic metastases ware(0.326±0.216),(0.373±0.298),respectively.There were significant differences(p<0.05)between HCC and Hepatic metastases in Ktrans,Vp and HPI values in both models.There were not statistically significant(p>0.05)between HCC and Hepatic metastases in Kep,Ve values.Drawed ROC curves of Ktrans,Vp,HPI,the Ktrans value(area under the curve of 0.869)among Extended Tofts model parameters was selected as optimal parameter to identify HCC and Hepatic metastases;the HPI value(area under the curve of 0.845)among Exchange model parameters was selected as optimal parameter to differentiate two tumors.The diagnostic accordance rate of Extended Tofts model and Exchange model were 80%(32/40),82.5%(33/40),respectively;There was no significant difference between them(χ2=0.082,p=0.775).Conclusion:Parameters including Ktrans,Vp,HPI of the Extended Tofts model and Exchange model in DCE-MRI perfusion can be used to identify HCC and Hepatic metastases of colorectal cancer.Among these parameters,Ktrans of Extended Tofts model and HPI of Exchange model have higher diagnostic value in differentiating HCC and Hepatic metastases of colorectal cancer.