Department of Surgical Sciences, University of Bologna, Italy; Department of Molecular and Medical Pharmacology, University of California Los Angeles, USA.
Nuclear Medicine Unit, S.Orsola-Malpighi Hospital, University of Bologna, Italy.
Methods. 2017 Nov 1;130:36-41. doi: 10.1016/j.ymeth.2017.07.009. Epub 2017 Jul 13.
Nowadays several new imaging modalities are available for investigating prostate cancer (PCa) such as magnet resonance imaging (MRI) in the form of whole body MRI and pelvic multiparametric MRI and positron emission tomography (PET) using choline as radiotracers. Nevertheless, these modalities proved sub-optimal accuracy for detecting PCa metastases, particularly in the recurrence setting. A new molecular probe targeting the prostate specific membrane antigen (PSMA) has been recently developed for PET imaging. PSMA, the glutamate carboxypeptidase II, is a membrane bound metallo-peptidase over-expressed in PCa cells. It has been shown that PSMA based imaging offers higher tumor detection rate compared to choline PET/CT and radiological conventional imaging, especially at very low PSA levels during biochemical recurrence. In addition PSMA, as theranostics agent, allows both radiolabeling with diagnostic (e.g. 68Ga, 18F) or therapeutic nuclides (e.g. 177Lu, 225Ac). Initial results show that PSMA-targeted radioligand therapy can potentially delay disease progression in metastatic castrate-resistant PCa. Despite still investigational, the bombesin-based radiotracers and antagonist of gastrin releasing-peptide receptor (GRP) (RM2) and anti1-amino-3-18Ffluorocyclobutane-1-carboxylic acid (18F-FACBC) are emerging as possible alternatives for investigating PCa. Considering the wide diffusion of PCa in the Europe and the United States, the presence of these new diagnostic techniques able to detect the disease with high sensitivity and specificity might have a clinical impact on the management of patients. PET/CT imaging with new radiopharmaceuticals can implement the patient management identifying lesion(s) not detectable with conventional imaging procedures. In this review article will be discussed the most promising new PET radiopharmaceuticals (68Ga-PSMA-11, 18F-FACBC, 68Ga-RM2) available at the moment, focusing the attention on their accuracy and their impact on treatment strategy.
目前，有几种新的成像方式可用于研究前列腺癌（PCa），例如全身 MRI 和盆腔多参数 MRI 形式的磁共振成像（MRI），以及使用胆碱作为放射性示踪剂的正电子发射断层扫描（PET）。然而，这些方式在检测 PCa 转移方面的准确性并不理想，特别是在复发情况下。最近，一种针对前列腺特异性膜抗原（PSMA）的新型分子探针已被开发用于 PET 成像。PSMA，即谷氨酸羧肽酶 II，是一种在 PCa 细胞中过度表达的膜结合金属肽酶。已经表明，与胆碱 PET/CT 和放射影像学常规成像相比，基于 PSMA 的成像提供了更高的肿瘤检测率，尤其是在生化复发期间 PSA 水平非常低的情况下。此外，PSMA 作为治疗剂，允许用诊断性（例如 68Ga、18F）或治疗性核素（例如 177Lu、225Ac）进行放射性标记。初步结果表明，PSMA 靶向放射性配体治疗可能延迟转移性去势抵抗性 PCa 的疾病进展。尽管仍在研究中，但基于蛙皮素的放射性示踪剂和胃泌素释放肽受体（GRP）拮抗剂（RM2）和抗 1-氨基-3-[18F]氟环丁烷-1-羧酸（18F-FACBC）作为研究 PCa 的可能替代物正在出现。考虑到 PCa 在欧洲和美国的广泛传播，这些新的诊断技术能够以高灵敏度和特异性检测疾病，可能会对患者的管理产生临床影响。使用新型放射性药物的 PET/CT 成像可以通过识别常规成像程序无法检测到的病变来实施患者管理。在这篇综述文章中，将讨论目前可用的最有前途的新型 PET 放射性药物（68Ga-PSMA-11、18F-FACBC、68Ga-RM2），重点关注它们的准确性及其对治疗策略的影响。
