摘要目的 探讨定量动态增强MRI鉴别乳腺良恶性病变的价值.方法 118例乳腺疾病患者行3.0 T定量动态增强MR检查,测量定量参数:容量转移常数(Ktrans)、速率常数(Kep)和血管外细胞外间隙容积比(Ve),对恶性病变、良性病变及正常腺体组间定量参数行单因素方差分析及LSD法两两比较;对浸润性癌与导管原位癌组间行独立样本t检验;最后绘制ROC曲线.结果 恶性病变组Ktrans、Ken、Ve均值分别为(1.010±0.580)min-1、(1.634±1.481)min-1、(0.735±0.273);良性病变组三者均值分别为(0.331±0.192)min-1、(0.417±0.324)min-1、(0.847±0.291);正常腺体组间三者均值分别为(0.051±0.028)min-1、(0.133±0.125)min-1、(0.597±0.354).正常腺体与良性病变、正常腺体与恶性病变及良性病变与恶性病变间Ktrans差异均有统计学意义(t值分别为9.681、11.189、5.590,P值均＜0.01);正常腺体与恶性病变、良性病变与恶性病变间Kep差异有统计学意义(t值分别为5.287、3.874,P值均＜0.05);正常腺体与良性病变、正常腺体与恶性病变间Ve差异有统计学意义(t值分别为2.932、2.562,P值均＜0.05);正常腺体与良性病变间Kep、良性病变与恶性病变间Ve差异无统计学意义(t值分别为0.760、0.832,P值均＞0.05).浸润性癌与导管原位癌组间Ktrans、Kep、Ve差异均无统计学意义(t值分别为0.834、0.075、0.454,P值均＞0.05).Ktrans、Kep、Ve三者ROC曲线下面积分别为0.934、0.941、0.659,以最大约登指数为最佳诊断切点值,则三者判断乳腺良恶性病变的敏感性分别为77.01%、91.95%、56.32%;特异性分别为95.65%、86.96%、78.26%.结论 定量动态增强参数Ktrans、Kep值可以对乳腺良恶性病变做出鉴别诊断,并表现出相对高的诊断效能,但对浸润性癌与导管原位癌鉴别效能较低.

abstractsObjective To evaluate the value of quantitative 3T dynamic contrast enhanced MRI in the diagnosis of breast lesions. Methods One-hundred and eighteen patients suspected of breast lesions underwent MRI examination. A 3.0 T MR scanner was used to obtain the quantitative MR pharmacokinetic parameters: Ktrans( volume transfer constant), Kep (exchange rate constant) and Ve (extravascular extracellular volume fraction). The mean Ktrans, Kep and Ve of malignant, benign and normal glandular tissues were calculated and compared each other using LSD method. Independent sample t test was used between invasive ductal carcinoma and ductal carcinoma in situ (microinvasion included). Finally, the areas under the ROC curve (AUC) of Ktrans, Kep and Ve between malignant and benign lesions were compared. Results The mean Ktrans, Kep and Ve of malignant lesions (n=87) were (1.010±0.580) min-1, (1.634 ± 1.481) min-1 and (0.735 ±0.273); the mean Ktrans, Kep and Ve of benign lesions (n=23) were (0.331±0.192) min - 1, (0.417±0.324) min - 1 and (0.847±0.291); and the mean Ktrans, Kep and Ve of normal glandular tissues (n =83) were (0.051 ±0.028) min-1, (0.133±0.125) min-1 and (0.597±0.354), respectively. There were significant differences between normal glandular tissues and benign lesions, normal glandular tissues and malignant lesions, benign and malignant lesions in Ktrans (t=9.681, 11.189, 5. 590, respectively, P ＜ 0. 01 ), normal glandular tissues and malignant lesions, benign and malignant lesions in Kep(t =5. 287, 3. 874, P＜0. 05). There were a statistic differences between normal glandular tissues and benign lesions, normal glandular tissues and malignant lesions in Ve(t =2. 932, 2. 562 ,P ＜0. 05). There were no significant differences between normal glandular tissues and benign lesions in Kep, benign and malignant lesions in Ve ( t = 0. 760, 0. 832, P ＞ 0.05 ),invasive ductal carcinoma and ductal carcinoma in situ (microinvasion included) in Ktrans, Kep and Ve(t =0.834,0.075,0.454,P＞0.05). The areas under the ROC curve (AUC) of Ktrans, Kep and Ve between malignant and benign lesions were 0. 934, 0. 941 and 0. 659. The sensitivity of Ktrans, Kep and Ve were 77.01% ,91.95% ,56. 32% and the specificity of Ktrans, Kep and Ve were 95. 65%, 86. 96%, 78.26% for the differential diagnosis of breast lesions if taken the maximum Youden's index as cut-off. Conclusion The differential diagnosis of benign and malignant breast lesions by Ktrans, Kep is applicable.