Department of Medical Imaging, Affiliated Hospital of Nantong University, NO. 20 Xisi Road, Nantong 226001, Jiangsu, People's Republic of China.
Department of Neurosurgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu, People's Republic of China.
Acad Radiol. 2019 Sep;26(9):1215-1221. doi: 10.1016/j.acra.2018.10.012. Epub 2018 Nov 8.
This study aimed to investigate whether volume transfer constant (K) and volume of extravascular extracellular space per unit volume of tissue (V) derived from dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) could quantitatively assess the tumor proliferation index (Ki-67) of gliomas noninvasively.
The preoperative DCE MRI data of 69 patients with pathologically confirmed glioma (28, 8, and 33 cases in grades Ⅱ, Ⅲ, and Ⅳ) were retrospectively reviewed. The maximal K and V were measured in the tumor body. The immunohistochemistry was used to detect the expression of Ki-67 proteins in glioma specimens. The Mann-Whitney U test was applied to analyze the differences in K, V, and Ki-67 index across histologically defined glioma grades. Spearman correlation was performed between K, V, and Ki-67 index. The receiver operating characteristic curve analysis was used to determine the cutoff values of K and V in distinguishing different Ki-67 index expression levels.
K, V, and Ki-67 index of grade Ⅱ (0.027 min, 0.065, 4.04%) were significantly lower than those of grade Ⅲ (0.093 min, 0.297, 25.13%) and Ⅳ (0.100 min, 0.299, 25.37%). Both K and V significantly correlated with the Ki-67 index in all tumors and high-grade gliomas (HGGs, grade Ⅲ and Ⅳ). The receiver operating characteristic curve analysis revealed that the cutoff values for K (0.079 min) and V (0.249) provided the best combination of sensitivity and specificity to distinguish the gliomas with high Ki-67 index from those with low Ki-67 index.
The DCE MRI-derived parameters were valuable in assessing the tumor cell proliferation in HGG noninvasively.
本研究旨在探讨动态对比增强磁共振成像（DCE MRI）得出的容积转移常数（K）和单位组织体积中外血管细胞外间隙体积（V）能否定量评估胶质瘤的肿瘤增殖指数（Ki-67）。
回顾性分析 69 例经病理证实的脑胶质瘤患者（28、8、33 例分别为 Ⅱ、Ⅲ、Ⅳ级）的术前 DCE MRI 数据。在肿瘤主体内测量最大 K 和 V。免疫组化检测胶质瘤标本中 Ki-67 蛋白的表达。采用 Mann-Whitney U 检验分析不同组织学分级的胶质瘤中 K、V 和 Ki-67 指数的差异。采用 Spearman 相关分析 K、V 和 Ki-67 指数之间的相关性。采用受试者工作特征曲线分析确定 K 和 V 区分不同 Ki-67 指数表达水平的截断值。
Ⅱ级（0.027 min，0.065，4.04%）的 K、V 和 Ki-67 指数明显低于Ⅲ级（0.093 min，0.297，25.13%）和Ⅳ级（0.100 min，0.299，25.37%）。所有肿瘤和高级别胶质瘤（HGG，Ⅲ级和Ⅳ级）中 K 和 V 与 Ki-67 指数均呈显著相关。受试者工作特征曲线分析显示，K（0.079 min）和 V（0.249）的截断值可最佳组合灵敏度和特异性，用于区分 Ki-67 指数高的胶质瘤和 Ki-67 指数低的胶质瘤。
DCE MRI 衍生参数可用于无创评估 HGG 的肿瘤细胞增殖。
