Department of Neurology, University Hospital of Cologne, Cologne, Germany.
Mol Imaging. 2011 Dec;10(6):453-9.
In patients with World Health Organization (WHO) grade III glioma with a lack of or minimal (< 1 cm3) magnetic resonance imaging (MRI) contrast enhancement, the volume of the metabolically active part of the tumor was assessed by [¹¹C]-methionine positron emission tomography (MET-PET). Eleven patients with WHO grade III gliomas underwent MET-PET and MRI (contrast-enhanced T1- and T2-weighted images). To calculate the volumes in cubic centimeters, threshold-based volume of interest analyses of the metabolically active tumor (MET uptake index ≥ 1.3), contrast enhancement, and the T2 lesion were performed after coregistration of all images. In all patients, the metabolically active tumor volume was larger than the volume of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) enhancement (20.8 ± 18.8 vs 0.29 ± 0.25 cm3; p < .001). With the exception of one patient, the volumes of contrast enhancement were located within the metabolically active tumor volume. In contrast, in the majority of patients, MET uptake overlapped with the T2 lesion and reached beyond it (in 10 of 12 MRIs/MET-PET scans). The present data suggest that in patients with WHO grade III glioma with minimal or a lack of contrast enhancement, MET-PET delineates metabolically active tumor tissue. These findings support the use of combined PET-MRI with radiolabeled amino acids (eg, MET) for the delineating of the true extent of active tumor in the diagnosis and treatment planning of patients with gliomas.
在缺乏或仅有轻微（<1cm³）磁共振成像（MRI）对比增强的世界卫生组织（WHO）III 级胶质瘤患者中，通过[¹¹C]-蛋氨酸正电子发射断层扫描（MET-PET）评估肿瘤代谢活跃部分的体积。11 例 WHO III 级胶质瘤患者接受了 MET-PET 和 MRI（对比增强 T1 和 T2 加权图像）检查。为了计算体积（以立方厘米为单位），在对所有图像进行配准后，对代谢活跃肿瘤（MET 摄取指数≥1.3）、对比增强和 T2 病变进行基于阈值的感兴趣区分析。在所有患者中，代谢活跃肿瘤的体积均大于钆二乙三胺五乙酸（Gd-DTPA）增强的体积（20.8±18.8 比 0.29±0.25cm³；p<.001）。除 1 例患者外，增强体积均位于代谢活跃肿瘤体积内。相比之下，在大多数患者中，MET 摄取与 T2 病变重叠并超出其范围（12 次 MRI/MET-PET 扫描中有 10 次）。目前的数据表明，在缺乏或仅有轻微对比增强的 WHO III 级胶质瘤患者中，MET-PET 可描绘代谢活跃的肿瘤组织。这些发现支持使用放射性标记氨基酸（如 MET）的 PET-MRI 联合技术，以在胶质瘤患者的诊断和治疗计划中描绘真正的活跃肿瘤范围。
