Radiologie, Hôpital Saint-Louis - Inserm U728 - Université Paris VII, 1 Avenue Claude Vellefaux, Paris, 75010, France.
BMC Cancer. 2011 Aug 19;11:361. doi: 10.1186/1471-2407-11-361.
To illustrate that Breast-MRI performed in high spatial resolution and low temporal resolution (1 minute) allows the measurement of kinetic parameters that can assess the final pathologic response to neoadjuvant chemotherapy in breast cancer.
Breast-MRI was performed in 24 women before and after treatment. Eight series of 1.11 minute-duration were acquired with a sub-millimeter spatial resolution. Transfer constant (K(trans)) and leakage space (V(e)) were calculated using measured and theoretical Arterial Input Function (AIF). Changes in kinetic parameters after treatment obtained with both AIFs were compared with final pathologic response graded in non-responder (< 50% therapeutic effect), partial-responder (> 50% therapeutic effect) and complete responder. Accuracies to identify non-responders were compared with receiver operating characteristic curves.
With measured-AIF, changes in kinetic parameters measured after treatment were in agreement with the final pathological response. Changes in V(e) and K(trans) were significantly different between non-(N = 11), partial-(N = 7), and complete (N = 6) responders, (P = 0.0092 and P = 0.0398 respectively). A decrease in V(e) of more than -72% and more than -84% for K(trans) resulted in 73% sensitivity for identifying non-responders (specificity 92% and 77% respectively). A decrease in V(e) of more than -87% helped to identify complete responders (Sensitivity 89%, Specificity 83%). With theoretical-AIF, changes in kinetic parameters had lower accuracy.
There is a good agreement between pathological findings and changes in kinetic parameters obtained with breast-MRI in high spatial and low temporal resolution when measured-AIF is used. Further studies are necessary to confirm whether MRI contrast kinetic parameters can be used earlier as a response predictor to neoadjuvant chemotherapy.
为了说明在高空间分辨率和低时间分辨率（1 分钟）下进行的乳房 MRI 能够测量动力学参数，这些参数可以评估乳腺癌新辅助化疗的最终病理反应。
对 24 例接受治疗前后的女性进行乳房 MRI 检查。采集 8 组时长为 1.11 分钟的亚毫米空间分辨率图像。使用测量和理论动脉输入函数（AIF）计算转移常数（K(trans)）和漏出空间（V(e)）。用两种 AIF 测量治疗后动力学参数的变化，并与非应答者（<50%治疗效果）、部分应答者（>50%治疗效果）和完全应答者的最终病理反应进行比较。通过受试者工作特征曲线比较识别非应答者的准确性。
使用测量的 AIF，治疗后动力学参数的变化与最终的病理反应一致。V(e)和 K(trans)的变化在非应答者（N=11）、部分应答者（N=7）和完全应答者（N=6）之间有显著差异（P=0.0092 和 P=0.0398）。V(e)下降超过-72%和 K(trans)下降超过-84%可使非应答者的识别率达到 73%（特异性分别为 92%和 77%）。V(e)下降超过-87%有助于识别完全应答者（灵敏度 89%，特异性 83%）。使用理论 AIF，动力学参数的变化准确性较低。
当使用测量的 AIF 时，高空间分辨率和低时间分辨率的乳房 MRI 获得的动力学参数变化与病理发现之间有很好的一致性。还需要进一步的研究来证实 MRI 对比动力学参数是否可以更早地作为新辅助化疗的反应预测指标。
