Baer A H, Hoff B A, Srinivasan A, Galbán C J, Mukherji S K
From the Department of Radiology (A.H.B., B.A.H., A.S., C.J.G.), University of Michigan Health System, Ann Arbor, Michigan
From the Department of Radiology (A.H.B., B.A.H., A.S., C.J.G.), University of Michigan Health System, Ann Arbor, Michigan.
AJNR Am J Neuroradiol. 2015 Apr;36(4):757-62. doi: 10.3174/ajnr.A4296. Epub 2015 Mar 19.
Estimating changes in the volume transfer constant, normalized area under the contrast-enhancement time curve at 60 seconds, and fractional blood plasma volume by using dynamic contrast-enhanced MR imaging may be useful in predicting tumor response to chemoradiation. We hypothesized that the parametric response map, a voxel-by-voxel analysis of quantitative dynamic contrast-enhanced MR imaging maps, predicts survival in patients with head and neck cancer.
Ten patients with locoregionally advanced head and neck squamous cell carcinoma underwent definitive concurrent chemoradiation therapy. For each patient, dynamic contrast-enhanced MR imaging data were collected before and 2 weeks after treatment initiation. Change in perfusion parameters within the primary tumor volume with time was analyzed by parametric response mapping and by whole-tumor mean percentage change. Outcome was defined as overall survival. The perfusion parameter and metric most predictive of outcome were identified. Overall survival was estimated by the log-rank test and Kaplan-Meier survival curve.
The volume transfer constant and normalized area under the contrast-enhancement time curve at 60 seconds were predictive of survival both in parametric response map analysis (volume transfer constant, P = .002; normalized area under the contrast-enhancement time curve at 60 seconds, P = .02) and in the percentage change analysis (volume transfer constant, P = .04; normalized area under the contrast-enhancement time curve at 60 seconds, P = .02). Blood plasma volume predicted survival in neither analysis.
Parametric response mapping of MR perfusion biomarkers could potentially guide treatment modification in patients with predicted treatment failure. Larger studies are needed to determine whether parametric response map analysis or percentage signal change in these perfusion parameters is the stronger predictor of survival.
利用动态对比增强磁共振成像估计容积转移常数、60秒时对比增强时间曲线下的标准化面积以及血浆容积分数的变化，可能有助于预测肿瘤对放化疗的反应。我们假设，参数反应图（一种对定量动态对比增强磁共振成像图进行逐像素分析的方法）可预测头颈部癌患者的生存率。
10例局部晚期头颈部鳞状细胞癌患者接受了根治性同步放化疗。对每位患者，在治疗开始前及开始后2周收集动态对比增强磁共振成像数据。通过参数反应图分析和全肿瘤平均百分比变化分析，研究原发肿瘤体积内灌注参数随时间的变化。结局定义为总生存期。确定最能预测结局的灌注参数和指标。通过对数秩检验和Kaplan-Meier生存曲线估计总生存期。
在参数反应图分析中（容积转移常数，P = .002；60秒时对比增强时间曲线下的标准化面积，P = .02）以及百分比变化分析中（容积转移常数，P = .04；60秒时对比增强时间曲线下的标准化面积，P = .02），容积转移常数和60秒时对比增强时间曲线下的标准化面积均能预测生存率。在两种分析中，血浆容积均不能预测生存率。
磁共振灌注生物标志物的参数反应图可能潜在地指导对预测治疗失败的患者进行治疗调整。需要开展更大规模的研究来确定参数反应图分析或这些灌注参数中的信号百分比变化是否是更强的生存预测指标。
