Department of Diagnostic Medicine, University of Texas at Austin, Austin, TX, USA; Livestrong Cancer Institutes, University of Texas at Austin, Austin, TX, USA; Department of Oncology, University of Texas at Austin, Austin, TX, USA.
Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
Eur J Radiol. 2021 Mar;136:109534. doi: 10.1016/j.ejrad.2021.109534. Epub 2021 Jan 9.
This study assesses the rate of enhancement of breast fibroglandular tissue after administration of a magnetic resonance imaging (MRI) gadolinium-based contrast agent and determines its relationship with response to neoadjuvant therapy (NAT) in women with breast cancer.
Women with locally advanced breast cancer (N = 19) were imaged four times over the course of NAT. Dynamic contrast-enhanced (DCE) MRI was acquired after administration of a gadolinium-based contrast agent with a temporal resolution of 7.27 s. The tumor, fibroglandular tissue, and adipose tissue were semi-automatically segmented using a manually drawn region of interest encompassing the tumor followed by fuzzy c-means clustering. The rate and relative intensity of signal enhancement were calculated for each voxel within the tumor and fibroglandular tissue.
The rate of fibroglandular tissue enhancement after contrast agent injection declined by an average of 29 % over the course of NAT. This decline was present in 16 of the 19 patients in the study. The rate of enhancement is significantly higher in women who achieve pathological complete response (pCR) after both 1 cycle (68 % higher, p < 0.05) and after 3-5 cycles of NAT (58 % higher; p < 0.05). The relative intensity of fibroglandular enhancement correlates with the rate of enhancement (R = 0.64, p < 0.001) and is higher in women who achieve pCR after both 1 cycle and after 3-5 cycles of NAT (p < 0.05, both timepoints).
The rate of fibroglandular tissue enhancement declines over the course of therapy, provides novel information not reflected by tumoral measures, and may predict pathological response early in the course of therapy, with smaller declines in enhancement in women who achieve favorable response.
本研究评估了乳腺纤维腺体组织在给予磁共振成像（MRI）钆基造影剂后增强的速度，并确定其与乳腺癌患者新辅助治疗（NAT）反应的关系。
19 例局部晚期乳腺癌女性在 NAT 过程中进行了 4 次成像。在给予钆基造影剂后，以 7.27s 的时间分辨率采集动态对比增强（DCE）MRI。使用手动绘制的 ROI 半自动分割肿瘤、纤维腺体组织和脂肪组织，然后使用模糊 C 均值聚类。在肿瘤和纤维腺体组织内的每个体素计算信号增强的速率和相对强度。
在 NAT 过程中，造影剂注射后纤维腺体组织增强的速度平均下降了 29%。在研究中的 19 名患者中有 16 名患者存在这种下降。在完成 1 个周期（增强率高 68%，p<0.05）和 3-5 个周期的 NAT（增强率高 58%；p<0.05）后获得病理完全缓解（pCR）的女性中，增强率显著更高。纤维腺体增强的相对强度与增强率相关（R=0.64，p<0.001），并且在完成 1 个周期和 3-5 个周期的 NAT 后获得 pCR 的女性中更高（p<0.05，两个时间点均如此）。
纤维腺体组织增强的速度在治疗过程中下降，提供了肿瘤测量无法反映的新信息，并且可能在治疗早期预测病理反应，增强下降较小的女性反应良好。
