比较乳腺动态增强MRI定量和半定量血流动力学参数鉴别乳腺良恶性病变

目的 比较乳腺动态增强MRI定量和半定量血流动力学参数鉴别诊断乳腺病变良恶性的效能。方法 采用杂合动态增强MR序列对59例患者共66个乳腺病变进行扫描,获得半定量参数和定量参数。半定量参数为时间-信号强度曲线（TIC）、初始增强曲线下面积（IAUGC）、最大增强斜率（MaxSlope）、对比增强比率（CER）及正向增强积分（PEI）;定量参数为前向容积转移常数（K^trans）、反向容积转移常数（K_ep）和每单位体积组织的血管外细胞外间隙容积（V_e）。以非参数检验比较良恶性病变间各参数的差异,并绘制ROC曲线,分析其诊断效能。结果 66个乳腺病变中,恶性31个（恶性组）,良性35个（良性组）,2组间K^trans、K_ep、TIC、IAUGC、MaxSlope差异均有统计学意义（P均<0.05）,V_e、PEI、CER差异无统计学意义（P均>0.05）;K^trans、K_ep、TIC、IAUGC、MaxSlope的AUC均>0.7。半定量参数联合诊断乳腺病变良恶性的AUC较单个参数均有显著提高（P均<0.05）;定量参数联合后的AUC较K^trans无显著提高（P=0.134）,较K_ep和V_e有显著提高（P均<0.001）。半定量联合与定量参数联合诊断诊断乳腺病变良恶性的AUC差异无统计学意义（P=0.614）。结论 K^trans、K_ep、TIC、IAUGC及MaxSlope对鉴别诊断乳腺良恶性病变具有较高效能;多参数联合,乳腺动态增强MRI半定量和定量参数诊断效能相似。

Comparison of quantitative and semi-quantitative hemodynamic parameters of dynamic contrast-enhanced MRI for differentiating benign and malignant breast lesions

Objective To compare the diagnostic performance of quantitative and semi-quantitative hemodynamic parameters of breast dynamic contrast-enhanced MRI (DCE-MRI) in differential diagnosis of benign and malignant breast lesions. Methods Fifty-nine patients (66 lesions) with breast lesions underwent hybrid DCE MRI with high temporal and spatial resolution, and semi-quantitative and quantitative hemodynamic parameters were obtained. The semi-quantitative parameters included time-intensity curve (TIC), initial area under the gadolinium curve (IAUGC), maximum slope of increase (MaxSlope), contrast enhancement rate (CER) and positive enhancement integral (PEI), while quantitative parameters included volume transfer constant (K^trans), rate constant (K_ep) and extravascular extracellular volume fraction (V_e). The differences of all the parameters between benign and malignant breast lesions were compared by using non-parametric tests. ROC was used to analyze the diagnostic performance. Results There were 31 malignant lesions (malignant group) and 35 benign ones (benign group). There were significant differences of K^trans, K_ep, TIC, IAUGC and MaxSlope between the two groups (all P<0.05), while no significant difference in V_e, PEI nor CER (all P>0.05). AUC of ROC curve of K^trans, K_ep, TIC, IAUGC and MaxSlope were all >0.7. AUC of semi-quantitative parameter combination in diagnosis of benign and malignant breast lesions were significantly higher than those of single parameter (all P<0.05), AUC of quantitative parameter in combination was not significantly higher than those of K^trans (P=0.134), but significantly higher than those of K_ep and V_e (all P<0 001). There was no significant difference in AUC between combined semi-quantitative and quantitative parameters in diagnosis of benign and malignant breast lesions (P=0.614). Conclusion K^trans, K_ep, TIC, IAUGC and MaxSlope have good diagnostic performance in differentiating benign and malignant breast lesions. The combined semi-quantitative and quantitative hemodynamic DCE-MRI parameters have similar diagnostic performance.