Zahra Mark A, Tan Li Tee, Priest Andrew N, Graves Martin J, Arends Mark, Crawford Robin A F, Brenton James D, Lomas David J, Sala Evis
Edinburgh Cancer Centre, Western General Hospital, Edinburgh, United Kingdom.
Int J Radiat Oncol Biol Phys. 2009 Jul 1;74(3):766-73. doi: 10.1016/j.ijrobp.2008.08.023. Epub 2008 Nov 18.
To evaluate semiquantitative and quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) measurements in predicting the response to radiotherapy in cervix cancer.
Patients with cervix cancer treated radically with chemoradiotherapy had DCE-MRI at three time points: before starting treatment, after 2 weeks of radiotherapy, and in the 5th week of radiotherapy. Semiquantitative measurements obtained from the signal intensity vs. time plots included arrival time of contrast, the slope and maximum slope of contrast uptake, time for peak enhancement, and the contrast enhancement ratio (CER). Pharmacokinetic modeling with a modeled vascular input function was used for the quantitative measurements volume transfer constant (K(trans)), rate constant (k(ep)), fraction plasma volume (fPV), and the initial area under gadolinium-time curve. The correlation of these measurements at each of the three time points with radiologic tumor response was investigated.
Thirteen patients had a total of 38 scans. There was no correlation between the DCE-MRI measurements and the corresponding tumor volumes. A statistically significant correlation with percentage tumor regression was shown with the pretreatment DCE-MRI semiquantitative parameters of peak time (p = 0.046), slope (p = 0.025), maximum slope (p = 0.046), and CER (p = 0.025) and the quantitative parameters K(trans) (p = 0.043) and k(ep) (p = 0.022). Second and third scan measurements did not show any correlation.
This is the first study to show that pretreatment DCE-MRI quantitative parameters predict the radiation response in cervix cancer. These measurements may allow a more meaningful comparison of DCE-MRI studies from different centers.
评估半定量和定量动态对比增强磁共振成像（DCE-MRI）测量在预测宫颈癌放疗反应中的作用。
接受根治性放化疗的宫颈癌患者在三个时间点进行DCE-MRI检查：治疗开始前、放疗2周后和放疗第5周。从信号强度与时间曲线获得的半定量测量包括对比剂到达时间、对比剂摄取斜率和最大斜率、峰值增强时间以及对比增强率（CER）。使用具有模拟血管输入函数的药代动力学模型进行定量测量，包括容积转移常数（K(trans)）、速率常数（k(ep)）、血浆容积分数（fPV）以及钆-时间曲线下的初始面积。研究这三个时间点的各项测量与肿瘤放射学反应之间的相关性。
13例患者共进行了38次扫描。DCE-MRI测量与相应肿瘤体积之间无相关性。治疗前DCE-MRI半定量参数峰值时间（p = 0.046）、斜率（p = 0.025）、最大斜率（p = 0.046）和CER（p = 0.025）以及定量参数K(trans)（p = 0.043）和k(ep)（p = 0.022）与肿瘤退缩百分比呈显著统计学相关性。第二次和第三次扫描测量未显示任何相关性。
这是第一项表明治疗前DCE-MRI定量参数可预测宫颈癌放疗反应的研究。这些测量可能有助于更有意义地比较不同中心的DCE-MRI研究。
