目的探讨定量动态增强磁共振 (DCE-MRI)感兴趣区(ROI)勾画技术在乳腺 癌诊断中的临床价值。方法 收集2015年 1月-2017年6月在我院行乳腺DCE-MRI检 查的57例女性患者，行感兴趣区(ROI)勾 画，测定容量转运常数(Ktrans)、反流速度 常数(Kep)、血管外细胞外间隙容积(Ve)， 比较乳腺癌、良性乳腺病变及正常腺体 上述参数差异，并采用ROC曲线分析各定 量参数对乳腺性质的诊断效能。结果 三 组Ktrans、Kep、Ve比较差异有统计学意义 (P<0.05)；良性病变组或乳腺癌组较正常 腺体组Ktrans、Kep明显增大(P<0.05)，Ve明 显减小(P<0.05)；乳腺癌组较良性病变组 Ktrans、Kep明显增大(P<0.05)，Ve明显减小 (P<0.05)。Ktrans、Kep、Ve诊断乳腺良恶性 的ROC曲线下面积分别为0.802、0.915、 0.736，敏感度分别为92.26%、92.34%、 83.17%，特异度分别为58.25%、74.68%、 66.62%；而Ktrans联合Kep诊断的ROC曲线 下面积为0.941，敏感度为97.33%，特异 度为83.49%。结论 DCE-MRI的定量参数 Ktrans、Kep、Ve对于乳腺良恶性诊断有重要 价值，且Ktrans联合Kep能够提高诊断效能。

Objective To explore the clinical value of quantitative dynamic contrastenhanced magnetic resonance imaging (DCE-MRI) region of interest (ROI) delineation in the diagnosis of breast cancer. Methods 57 female patientsexamined by DCE-MRI in the hospital from January 2015 to June 2017 were selected, and ROI delineation was performed. The volume transfer constant (Ktrans), reflux velocity constant (Kep) and extravascular space volume (Ve) were measured. The above parameters were compared among breast cancer, benign breast lesions and normal glands. The diagnostic efficiencies of different quantitative parameters for breast properties were analyzed by ROC curve. Results There were statistically significant differences of Ktrans, Kep and Ve among the three groups (P<0.05). The Ktrans and Kep showed the breast cancer group > the benign lesion group > the normal gland group (P<0.05), while Ve showed the breast cancer group < the benign lesion group < the normal gland group (P<0.05). The areas under ROC curve of Ktrans, Kep and Ve in the diagnosis of benign and malignant breast lesions were 0.802, 0.915 and 0.736 respectively, the sensitivities were 92.26%, 92.34% and 83.17% respectively, and the specificities were 58.25%, 74.68% and 66.62%, respectively. The area under ROC curve of Ktrans combined with Kep was 0.941, the sensitivity and specificity were 97.33% and 83.49% respectively. Conclusion The quantitative parameters of DCE-MRI, Ktrans, Kep and Ve are of great value in the diagnosis of benign and malignant breast lesions. Besides, Ktrans combined with Kep can improve the diagnostic efficiency.