METHODS: A cohort of 21 glioblastoma patients (mean age: 59.2 ± 11.8, 12 Male, 9 Female) that underwent treatment with bevacizumab were selected. The ADC values were calculated from the DWI images obtained from a standardized brain protocol across 1.5-T and 3-T MRI scanners. Ratios were calculated for rADC values. Lesions were classified as bevacizumab-induced cytotoxicity based on characteristic imaging features (well-defined regions of restricted diffusion with persistent diffusion restriction over the course of weeks without tissue volume loss and absence of contrast enhancement). The rADC value was compared to these values in radiation necrosis and recurrent lesions, which were concluded in our prior study. The nonparametric Wilcoxon signed rank test with p < 0.05 was used for significance.
RESULTS: The mean ± SD age of the selected patients was 59.2 ± 11.8. ADC values and corresponding mean rADC values for bevacizumab-induced cytotoxicity were 248.1 ± 67.2 and 0.39 ± 0.10, respectively. These results were compared to the ADC values and corresponding mean rADC values of tumor progression and radiation necrosis. Significant differences between rADC values were observed in all three groups (p < 0.001). Bevacizumab-induced cytotoxicity had statistically significant lower ADC values compared to both tumor recurrence and radiation necrosis.
CONCLUSIONS: The study demonstrates the potential of ADC values as noninvasive imaging biomarkers for differentiating recurrent glioblastoma from radiation necrosis and bevacizumab-induced cytotoxicity.
方法:21名胶质母细胞瘤患者(平均年龄:59.2±11.8,12名男性,选择接受贝伐单抗治疗的9名女性)。ADC值是从通过1.5T和3TMRI扫描仪的标准化脑方案获得的DWI图像计算的。计算rADC值的比率。基于特征性成像特征(明确限定的受限扩散区域,在数周的过程中具有持续的扩散限制,没有组织体积损失和没有对比增强),将病变分类为贝伐单抗诱导的细胞毒性。将rADC值与放射性坏死和复发性病变中的这些值进行比较,这是在我们之前的研究中得出的结论。p<0.05的非参数Wilcoxon符号秩检验用于显著性。
结果:所选患者的平均±SD年龄为59.2±11.8。贝伐单抗诱导的细胞毒性的ADC值和相应的平均rADC值分别为248.1±67.2和0.39±0.10。将这些结果与肿瘤进展和放射坏死的ADC值和相应的平均rADC值进行比较。在所有三组中观察到rADC值之间的显着差异(p<0.001)。与肿瘤复发和放射坏死相比,贝伐单抗诱导的细胞毒性具有统计学上显著较低的ADC值。
结论:该研究表明ADC值作为非侵入性成像生物标志物,用于区分复发性胶质母细胞瘤与放射性坏死和贝伐单抗诱导的细胞毒性。