Department of Radiology, Kwandong University, College of Medicine, Myongji Hospital, Koyang City, Gyunggi-Do, South Korea.
AJR Am J Roentgenol. 2011 Jan;196(1):71-6. doi: 10.2214/AJR.10.4752.
In glioblastoma multiforme, the peritumoral region may be infiltrated with malignant cells in addition to vasogenic edema, whereas in a metastatic deposit, the peritumoral areas comprise predominantly vasogenic edema. The purpose of this study was to determine whether the minimum apparent diffusion coefficient (ADC) can be used to differentiate glioblastoma from solitary metastasis on the basis of cellularity levels in the enhancing tumor and in the peritumoral region.
Seventy-three patients underwent conventional MRI and diffusion-weighted imaging (DWI) before undergoing treatment. The minimum ADC was measured in the enhancing tumor, peritumoral region, and contralateral normal white matter. To determine whether there was a statistical difference between metastasis and glioblastoma, we analyzed patient age and sex, minimum ADC value, and ADC ratio of the two groups. A receiver operating characteristic (ROC) curve analysis was used to determine the cutoff value of the minimum ADC that had the best combination of sensitivity and specificity for distinguishing between glioblastoma and metastasis.
The mean minimum ADC values and mean ADC ratios in the peritumoral regions of glioblastomas were significantly higher than those in metastases. However, the mean minimum ADC values and mean ADC ratios in enhancing tumors showed no statistically significant difference between the two groups. According to ROC curve analysis, a cutoff value of 1.302 × 10(-3) mm(2)/s for the minimum peritumoral ADC value generated the best combination of sensitivity (82.9%) and specificity (78.9%) for distinguishing between glioblastoma and metastasis.
Although the characteristics of solitary metastasis and glioblastoma multiforme may be similar on conventional MRI, DWI can offer diagnostic information to distinguish between the tumors.
在多形性胶质母细胞瘤中，除血管源性水肿外，肿瘤周围区域可能还浸润有恶性细胞，而在转移性病灶中，肿瘤周围区域主要包含血管源性水肿。本研究旨在确定最小表观扩散系数（ADC）是否可基于增强肿瘤和肿瘤周围区域的细胞密度来区分胶质母细胞瘤和单发转移。
73 例患者在接受治疗前均进行了常规 MRI 和弥散加权成像（DWI）检查。在增强肿瘤、肿瘤周围区域和对侧正常白质中测量最小 ADC。为了确定转移和胶质母细胞瘤之间是否存在统计学差异，我们分析了患者的年龄和性别、最小 ADC 值以及两组的 ADC 比值。采用受试者工作特征（ROC）曲线分析确定最佳组合的最小 ADC 截断值，该截断值在区分胶质母细胞瘤和转移瘤方面具有最佳的敏感性和特异性。
胶质母细胞瘤肿瘤周围区域的最小 ADC 值和 ADC 比值的平均值明显高于转移瘤。然而，两组增强肿瘤的最小 ADC 值和 ADC 比值的平均值无统计学差异。根据 ROC 曲线分析，最小肿瘤周围 ADC 值的截断值为 1.302×10(-3)mm(2)/s 时，可获得区分胶质母细胞瘤和转移瘤的最佳敏感性（82.9%）和特异性（78.9%）的组合。
尽管单发转移和多形性胶质母细胞瘤的常规 MRI 特征可能相似，但 DWI 可提供有助于区分肿瘤的诊断信息。
