Cancer Research UK and EPSRC Imaging Centre and Drug Development Unit of Section of Medicine, Institute of Cancer Research and Royal Marsden Hospital, MRI Unit, Downs Road, Sutton, Surrey SM2 5PT, England.
Radiology. 2012 Nov;265(2):426-36. doi: 10.1148/radiol.12112565. Epub 2012 Aug 13.
To assess baseline reproducibility and compare performance of dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging versus DCE computed tomographic (CT) measures of early vascular response in the same patients treated with cediranib (30 or 45 mg daily).
After institutional review board approval, written informed consent was obtained from 29 patients with advanced solid tumors who had lesions 3 cm or larger and in whom simultaneous imaging of an adjacent artery was possible. Two baseline DCE MR acquisitions and two baseline DCE CT acquisitions 7 days or fewer apart (within 14 days of starting treatment) and two posttreatment acquisitions with each modality at day 7 and 28 (±3 days) were obtained. Nonmodeled and modeled parameters were derived (measured arterial input function [AIF] for CT, population-based AIF for MR imaging; temporal sampling rate of 0.5 second for CT, 3-6 seconds for MR imaging). Baseline variability was assessed by using intra- and intersubject analysis of variance and Bland-Altman analysis; a paired t test assessed change from baseline to after treatment.
The most reproducible parameters were DCE MR imaging enhancement fraction (baseline intrapatient coefficient of variation [CV]=8.6%), volume transfer constant (CV=13.9%), and integrated area under the contrast agent uptake curve at 60 seconds (CV=15.5%) and DCE CT positive enhancement integral (CV=16.0%). Blood plasma volume was highly variable and the only parameter with CV greater than 30%. Average reductions (percentage change) from baseline were consistently observed for all DCE MR imaging and DCE CT parameters at day 7 and 28 for both starting-dose groups (45 and 30 mg), except for DCE CT mean transit time. Percentage change from baseline for parameters reflecting blood flow and permeability were comparable, and reductions from baseline at day 7 were maintained at day 28.
DCE MR imaging and DCE CT can depict vascular response to antiangiogenic agents with response evident at day 7. Improved reproducibility with MR imaging favors its use in trials with small patient numbers.
评估基线可重复性，并比较同一组接受西地尼布（每日 30 或 45mg）治疗的患者中，动态对比增强（DCE）磁共振（MR）成像与 DCE 计算机断层扫描（CT）测量早期血管反应的性能。
经机构审查委员会批准，对 29 例接受治疗的晚期实体瘤患者进行了书面知情同意，这些患者的病变直径为 3cm 或以上，并且可以同时对相邻动脉进行成像。在治疗开始后 7 天内（不超过 14 天），对每个患者进行两次基线 DCE-MR 采集和两次基线 DCE-CT 采集，然后在第 7 天和第 28 天（±3 天）分别用两种模态进行两次治疗后采集。对非模型和模型参数进行了推导（CT 采用测量动脉输入函数[测量动脉输入函数]，MR 成像采用基于人群的动脉输入函数；CT 为 0.5 秒，MR 成像为 3-6 秒）。通过对个体内和个体间的方差分析和 Bland-Altman 分析评估了基线变异性；配对 t 检验评估了从基线到治疗后的变化。
最具可重复性的参数是 DCE-MR 成像增强分数（基线个体内变异系数[CV]=8.6%）、容积转移常数（CV=13.9%）和 60 秒时对比剂摄取曲线下的积分面积（CV=15.5%）和 DCE-CT 阳性增强积分（CV=16.0%）。血容量变化很大，是唯一 CV 大于 30%的参数。对于起始剂量为 45mg 和 30mg 的两组患者，在第 7 天和第 28 天，所有 DCE-MR 成像和 DCE-CT 参数的平均值都观察到了从基线的持续降低（百分比变化），除了 DCE-CT 平均通过时间。反映血流和通透性的参数的基线百分比变化相当，并且第 7 天的基线降低在第 28 天保持不变。
DCE-MR 成像和 DCE-CT 可以描绘抗血管生成药物对血管的反应，在第 7 天即可观察到反应。MR 成像的可重复性提高有利于其在患者数量较少的试验中使用。
