Suh C H, Kim H S, Choi Y J, Kim N, Kim S J
Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
AJNR Am J Neuroradiol. 2013 Dec;34(12):2278-86. doi: 10.3174/ajnr.A3634. Epub 2013 Jul 4.
Dynamic contrast-enhanced T1-weighted perfusion MR imaging is much less susceptible to artifacts, and its high spatial resolution allows accurate characterization of the vascular microenvironment of the lesion. The purpose of this study was to test the predictive value of the initial and final area under the time signal-intensity curves ratio derived from dynamic contrast-enhanced perfusion MR imaging to differentiate pseudoprogression from early tumor progression in patients with glioblastomas.
Seventy-nine consecutive patients who showed new or enlarged, contrast-enhancing lesions within the radiation field after concurrent chemoradiotherapy were assessed by use of conventional and dynamic contrast-enhanced perfusion MR imaging. The bimodal histogram parameters of the area under the time signal-intensity curves ratio, which included the mean area under the time signal-intensity curves ratio at a higher curve (mAUCRH), 3 cumulative histogram parameters (AUCR50, AUCR75, and AUCR90), and the area under the time signal-intensity curves ratio at mode (AUCRmode), were calculated and correlated with the final pathologic or clinical diagnosis. The best predictor for differentiation of pseudoprogression from early tumor progression was determined by receiver operating characteristic curve analyses.
Seventy-nine study patients were subsequently classified as having pseudoprogression (n=37, 46.8%) or early tumor progression (n=42, 53.2%). There were statistically significant differences of mAUCRH, AUCR50, AUCR75, AUCR90, and AUCRmode between the 2 groups (P < .0001, each). Receiver operating characteristic curve analyses showed the mAUCRH to be the best single predictor of pseudoprogression, with a sensitivity of 90.1% and a specificity of 82.9%. AUCR50 was found to be the most specific predictor of pseudoprogression, with a sensitivity of 87.2% and a specificity of 83.1%.
A bimodal histogram analysis of the area under the time signal-intensity curves ratio derived from dynamic contrast-enhanced perfusion MR imaging can be a potential, noninvasive imaging biomarker for monitoring early treatment response in patients with glioblastomas.
动态对比增强T1加权灌注磁共振成像对伪影的敏感性低得多，其高空间分辨率能够准确地描述病变的血管微环境。本研究的目的是检验动态对比增强灌注磁共振成像得出的时间信号强度曲线比值的初始值和终末值对胶质母细胞瘤患者区分假性进展与早期肿瘤进展的预测价值。
对79例在同步放化疗后放疗野内出现新的或增大的强化病变的连续患者进行常规和动态对比增强灌注磁共振成像评估。计算时间信号强度曲线比值的双峰直方图参数，包括较高曲线下的时间信号强度曲线比值的平均面积（mAUCRH）、3个累积直方图参数（AUCR50、AUCR75和AUCR90）以及峰处的时间信号强度曲线比值面积（AUCRmode），并将其与最终病理或临床诊断相关联。通过受试者工作特征曲线分析确定区分假性进展与早期肿瘤进展的最佳预测指标。
79例研究患者随后被分类为假性进展（n = 3７，46.8%）或早期肿瘤进展（n = 42，53.2%）。两组之间的mAUCRH、AUCR50、AUCR75、AUCR90和AUCRmode存在统计学显著差异（均P < .0001）。受试者工作特征曲线分析显示，mAUCRH是假性进展的最佳单一预测指标，敏感性为90.1%，特异性为82.9%。AUCR50被发现是假性进展最具特异性的预测指标，敏感性为87.2%，特异性为83.1%。
动态对比增强灌注磁共振成像得出的时间信号强度曲线比值的双峰直方图分析可能是监测胶质母细胞瘤患者早期治疗反应的一种潜在的非侵入性成像生物标志物。
