Lilja A, Bergström K, Hartvig P, Spännare B, Halldin C, Lundqvist H, Långstrom B
AJNR Am J Neuroradiol. 1985 Jul-Aug;6(4):505-14.
The regional kinetics of intravenously injected L-methyl-11C-methionine (11C-L-methionine) in the brain was investigated by positron emission tomography (PET) in 14 patients with gliomas. In both tumor and unaffected brain the tracer uptake reached a nearly constant level in 5 min or less. The ratio between the uptake of 11C-L-methionine by high-grade tumors and the uptake by unaffected brain was 1.9-4.8. In two cases of low-grade astrocytoma the ratio was 0.8-1.0. High uptakes of 11C-L-methionine occurred in gliomas even in the absence of blood-brain barrier defects as observed by other methods. This indicates that besides active transport of amino acid, a larger extracellular space in tumor as compared with unaffected brain tissue may also contribute to the increased uptake of 11C-L-methionine--derived radioactivity. In some patients delineation of the tumors was improved by use of PET with 11C-L-methionine as compared with computed tomography, angiography, and, in some instances, PET with 68Ga-EDTA. PET with 11C-L-methionine permits better evaluation of the tumor extent and may affect preoperative grading.
通过正电子发射断层扫描（PET）对14例脑胶质瘤患者静脉注射L-甲基-11C-蛋氨酸（11C-L-蛋氨酸）后的脑内区域动力学进行了研究。在肿瘤和未受影响的脑组织中，示踪剂摄取在5分钟或更短时间内达到几乎恒定的水平。高级别肿瘤对11C-L-蛋氨酸的摄取与未受影响脑组织的摄取之比为1.9至4.8。在两例低级别星形细胞瘤中，该比值为0.8至1.0。即使通过其他方法未观察到血脑屏障缺陷，脑胶质瘤中也会出现11C-L-蛋氨酸的高摄取。这表明，除了氨基酸的主动转运外，与未受影响的脑组织相比，肿瘤中更大的细胞外间隙也可能导致11C-L-蛋氨酸衍生放射性摄取增加。与计算机断层扫描、血管造影以及在某些情况下与68Ga-EDTA PET相比，在一些患者中，使用11C-L-蛋氨酸PET可改善肿瘤的轮廓显示。11C-L-蛋氨酸PET能够更好地评估肿瘤范围，并可能影响术前分级。
