Stegmayr Carina, Willuweit Antje, Lohmann Philipp, Langen Karl-Josef
Institute of Neuroscience and Medicine 4, Forschungszentrum Juelich, Juelich, Germany.
Department of Nuclear Medicine, University of Aachen, Aachen, Germany.
Curr Radiopharm. 2019;12(3):201-210. doi: 10.2174/1874471012666190111111046.
In recent years, PET using radiolabelled amino acids has gained considerable interest as an additional tool besides MRI to improve the diagnosis of cerebral gliomas and brain metastases. A very successful tracer in this field is O-(2-[18F]fluoroethyl)-L-tyrosine (FET) which in recent years has replaced short-lived tracers such as [11C]-methyl-L-methionine in many neuro-oncological centers in Western Europe. FET can be produced with high efficiency and distributed in a satellite concept like 2- [18F]fluoro-2-deoxy-D-glucose. Many clinical studies have demonstrated that FET PET provides important diagnostic information regarding the delineation of cerebral gliomas for therapy planning, an improved differentiation of tumor recurrence from treatment-related changes and sensitive treatment monitoring. In parallel, a considerable number of experimental studies have investigated the uptake mechanisms of FET on the cellular level and the behavior of the tracer in various benign lesions in order to clarify the specificity of FET uptake for tumor tissue. Further studies have explored the effects of treatment related tissue alterations on tracer uptake such as surgery, radiation and drug therapy. Finally, the role of blood-brain barrier integrity for FET uptake which presents an important aspect for PET tracers targeting neoplastic lesions in the brain has been investigated in several studies. Based on a literature research regarding experimental FET studies and corresponding clinical applications this article summarizes the knowledge on the uptake behavior of FET, which has been collected in more than 30 experimental studies during the last two decades and discusses the role of these results in the clinical context.
近年来，使用放射性标记氨基酸的正电子发射断层扫描（PET）作为磁共振成像（MRI）之外的一种辅助工具，在改善脑胶质瘤和脑转移瘤的诊断方面引起了广泛关注。在这一领域，一种非常成功的示踪剂是O-(2-[18F]氟乙基)-L-酪氨酸（FET），近年来，在西欧的许多神经肿瘤中心，它已取代了诸如[11C]-甲基-L-蛋氨酸等半衰期短的示踪剂。FET能够高效生产，并以类似于2-[18F]氟-2-脱氧-D-葡萄糖的卫星概念进行分布。许多临床研究表明，FET PET在脑胶质瘤的治疗规划中，为肿瘤轮廓的描绘提供了重要的诊断信息，在区分肿瘤复发与治疗相关变化以及敏感的治疗监测方面有所改进。与此同时，大量的实验研究在细胞水平上研究了FET的摄取机制以及该示踪剂在各种良性病变中的行为，以阐明FET对肿瘤组织摄取的特异性。进一步的研究探讨了治疗相关的组织改变对示踪剂摄取的影响，如手术、放疗和药物治疗。最后，在几项研究中还调查了血脑屏障完整性对FET摄取的作用，这是针对脑部肿瘤性病变的PET示踪剂的一个重要方面。基于对FET实验研究及相应临床应用的文献调研，本文总结了有关FET摄取行为的知识，这些知识是在过去二十年中超过30项实验研究中收集到的，并讨论了这些结果在临床背景中的作用。
