Correlation Between Dynamic Contrast-enhanced MRI Quantitative Parameters And Ki67、HER-2 In Rectal Cancer

Objective To evaluate the association between DCE-MRI quantitative parameters(Ktrans、Ve and Kep) and degree of histologic differentiation, and with and without lymph node metastasis, and the expression of molecular biological markers Ki67 and HER-2 for rectal cancer. To analysis the internal relation between imaging parameters and the tumor biological behavior, so as to evaluate rectal cancer prognosis indirectly by imaging examination means and improve the application value of DCE-MRI in clinical diagnosis and treatment.Materials and Methods Gathering 94 cases of rectal cancer patients who underwent dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) examination. On the one hand, we measured the quantitative parameters Ktrans value、Vevalue and Kepvalue of all patients with rectal cancer tumor tissues in the DCE-MRI. On the other hand, we detected the molecular markers Ki67 and HER-2 expression by immunohistochemical SP staining.And we analyzed the correlation between DCE MRI quantitative parameters(Ktrans value, Veand Kepvalue) and tissue differentiation degree, expression of molecular markers Ki67 and HER-2 in rectal cancer.All data processed software by SPSS 17.0, using ANOVA and the independent sample t-test, nonparametric Spearman rank correlation analysis and other statistical methods.Results1、There are 94 cases of patients with rectal cancer by histopathological staging, Ktrans values were respectively(0.159±0.034) min-1,(0.239±0.069) min-1and(0.372±0.088) min-1, there were significant difference statistically significant(P<0.01),others were not. A increase in the Ktrans, Ve and Kepvalue of rectal cancer DCE-MRI with histopathological differentiation decrease, and Ktrans value had significant statistical significance. Nonparametric Spearman correlation coefficient in DCE MRI quantitative parameter showed Ktrans value, Ve and Kep have positive correlation with rectal cancer pathological tissue differentiation degree.2、 DCE MRI quantitative parameter value Ktrans was significant statistical significance in different expression level of Ki67(P<0.01), Ve and Kep were not(P=0.277, P=0.084), thecorrelation analysis showed that the quantitative parameters Ktrans and Kep value were strong positive correlate to Ki67(r=0.549, P=0.000; r=0.282, P=0.006); Ktrans and Kepvalues were significant statistical significance in different HER-2 expression level(P<0.01), Vewas not; Ktrans,and Kep were positively correlated to HER-2 positive expression(r=0.538, P=0.000; r=0.222,P=0.031), Vewas not.3、Ktrans and Kepwere significant statistical significance between lymph node metastasis or not(P< 0.01); and whether lymph node metastasis was positively correlated to molecular markers Ki67、HER-2(r=0.234, P=0.023; r=0.282, P=0.006).4、The expression of Ki67 was strong positive correlate to HER-2(r= 0.363, P=0.363).Conclusion DCE-MRI quantitative parameters of rectal cancer can reflect tumor microvascular perfusion, blood vessels, histopathological differentiation degree, and indirectly measure the biological behavior of rectal cancer tumor tissue. At the same time, the molecular markers Ki67 and HER-2 were promoting role in rectal cancer growth.