Gaustad Jon-Vidar, Benjaminsen Ilana C, Graff Bjørn A, Brurberg Kjetil G, Ruud Else-Beate M, Rofstad Einar K
Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, Oslo, Norway.
J Magn Reson Imaging. 2005 Jun;21(6):792-800. doi: 10.1002/jmri.20321.
To determine the intratumor heterogeneity in blood perfusion of orthotopic human melanoma xenografts by use of gadopentetate dimeglumine (Gd-DTPA)-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).
Orthotopic xenografts of an amelanotic human melanoma cell line (A-07) were scanned sagittally, coronally, and axially in three subsequent DCE-MRI sessions, using spoiled gradient recalled sequences, a voxel size of 0.31x0.62x2.0 mm3, and an interleaving acquisition method to avoid slice gaps. Tumor images of E . F (E is initial extraction fraction and F is perfusion) were produced by subjecting the DCE-MRI data to Kety analysis. E . F was used as a parameter for tumor blood perfusion, since E for Gd-DTPA is close to unity in A-07 tumors.
All A-07 tumors subjected to investigation showed anisotropic radial heterogeneity in blood perfusion. The blood perfusion was low in the center of the tumors and increased toward the tumor periphery in the cranial, dorsal, caudal, and ventral directions, but not in the lateral and medial directions. In addition, 9 of 10 tumors showed blood perfusion hot spots in central or nonperipheral regions. The hot spots differed significantly between tumors in size, shape, location, and intensity, and appeared to be governed by stochastic processes. This heterogeneity superimposed the radial heterogeneity, but did not overshadow it in any tumor.
Orthotopic human melanoma xenografts show significant intratumor heterogeneity in blood perfusion. This heterogeneity is made up of two distinctly different components, one stochastic and one nonstochastic radial component. The radial component is anisotropic and dominant and is superimposed by the stochastic component.
通过使用基于钆喷酸葡胺（Gd-DTPA）的动态对比增强磁共振成像（DCE-MRI）来确定原位人黑色素瘤异种移植瘤内血液灌注的肿瘤内异质性。
在三个连续的DCE-MRI检查中，对无黑色素的人黑色素瘤细胞系（A-07）的原位异种移植瘤进行矢状面、冠状面和轴位扫描，使用扰相梯度回波序列，体素大小为0.31×0.62×2.0 mm³，并采用交错采集方法以避免层间间隙。通过对DCE-MRI数据进行凯氏分析生成E.F（E为初始提取分数，F为灌注）的肿瘤图像。由于在A-07肿瘤中Gd-DTPA的E接近1，因此E.F被用作肿瘤血液灌注的参数。
所有接受研究的A-07肿瘤在血液灌注方面均表现出各向异性的径向异质性。肿瘤中心的血液灌注较低，在颅侧、背侧、尾侧和腹侧方向上朝着肿瘤周边增加，但在外侧和内侧方向上没有增加。此外，10个肿瘤中有9个在中央或非周边区域显示出血液灌注热点。这些热点在不同肿瘤之间的大小、形状、位置和强度存在显著差异，并且似乎受随机过程支配。这种异质性叠加在径向异质性之上，但在任何肿瘤中都没有掩盖它。
原位人黑色素瘤异种移植瘤在血液灌注方面表现出显著的肿瘤内异质性。这种异质性由两个明显不同的成分组成，一个是随机成分，一个是非随机的径向成分。径向成分是各向异性的且占主导地位，并被随机成分叠加。
