1.5T MRI平扫及动态增强扫描在乳腺癌早期诊断中的应用

Application of 1.5T MRI Plain Scan and Dynamic Contrast-enhanced Scan in the Early Diagnosis of Breast Cancer

目的探讨磁共振成像(MRI)及动态对比增强(DCE)应用于早期乳腺癌诊断的临床效果。方法回顾性分析106例早期乳腺癌患者临床资料,并纳入同期确诊的74例乳腺良性肿瘤患者作为对照,比较良恶性乳腺肿瘤及不同组织学分级下乳腺癌MRI平扫影像特征与DCE[转运常数(K^trans)、速率常数(Kep)、血管外细胞间隙体积分数(Ve)]差异,评估DCE定量参数鉴别良恶性乳腺肿瘤的诊断效能,并分析乳腺癌组织学分型与DCE定量参数的相关性。结果良恶性乳腺肿瘤肿瘤直径及Ve水平比较均无统计学意义(P>0.05),而肿瘤形态与肿瘤边缘比较均有统计学意义(P<0.05),且乳腺癌K^trans、Kep水平均明显高于乳腺良性肿瘤(P<0.05)。K^trans、Kep鉴别诊断良恶性乳腺肿瘤受试者工作特征(ROC)曲线下面积(AUC)均明显大于参考线(P<0.05),诊断灵敏度分别为75.47%、64.15%,特异度分别为86.49%、93.24%,截断值分别为>0.515 min-1、>1.184 min-1。不同组织学分级乳腺癌肿瘤直径、肿瘤形态、肿瘤边缘及Ve水平比较均无统计学意义(P>0.05),而组织学Ⅰ/Ⅱ级乳腺癌K^trans、Kep水平均明显低于组织学Ⅲ级(P<0.05)。乳腺癌K^trans、Kep水平与组织学分级呈显著正相关性(γ>0,P<0.05),而Ve水平与组织学分级无显著相关性(P>0.05)。结论1.5T MRI平扫与DCE能有效鉴别良恶性乳腺肿瘤,其中DCE定量参数还与乳腺癌组织学分级密切相关,可为临床早期诊断与预后分析提供参考。

Objective To explore the clinical effects of magnetic resonance imaging(MRI)and dynamic contrast-enhanced(DCE)in the diagnosis of early breast cancer.Methods The clinical data of 106 patients with early breast cancer were retrospectively analyzed.74 patients with benign breast tumors diagnosed at the same time were included as controls.The imaging features of MRI plain scan and DCE parameters[transfer constant(K^trans),rate constant(Kep),extravascular extracellular space volume fraction(Ve)]were compared between benign and malignant breast tumors and different histological grades of breast cancer,and the diagnostic efficacy of DCE quantitative parameters was evaluated in differential diagnosis of benign and malignant breast tumors,and the correlation between histological grades of breast cancer and DCE quantitative parameters was analyzed.Results There were no significant differences in tumor diameter and Velevel between benign and malignant breast tumors(P>0.05),and there were statistically significant differences in the tumor morphology and tumor margin(P<0.05),and the levels of K^transand Kep of breast cancer were significantly higher than those of benign breast tumors(P<0.05).The vales of area under receiver operating characteristic(ROC)curve(AUC)of K^transand Kepwere significantly larger than the reference line in the differential diagnosis of benign and malignant breast tumors(P<0.05),and the diagnostic sensitivities were 75.47%and 64.15%,and the specificities were 86.49%and 93.24%,and the cutoff values were>0.515 min-1 and>1.184 min-1.There were no significant differences in tumor diameter,tumor morphology,tumor margin and Ve level among different histological grades of breast cancer(P>0.05),and the levels of K^transand Kepin histological gradeⅠ/Ⅱbreast cancer were significantly lower than those in histological gradeⅢ(P<0.05).The levels of K^transand Kepwere significantly positively correlated with histological grades of breast cancer(γ>0,P<0.05),but there was no significant correlation between Ve level and histological grades(P>0.05).Conclusion 1.5 T MRI plain scan and DCE can effectively identify benign and malignant breast tumors.The quantitative parameters of DCE are also closely related to the histological grades of breast cancer,which can provide reference for early clinical diagnosis and prognosis analysis.