Radiolabeled prostate-specific membrane antigen small-molecule inhibitors.

Prostate cancer (PC) is one of the most common malignancies worldwide. Prostate-specific membrane antigen (PSMA) has been found to be expressed in most PCs and represents an ideal target for diagnostic and therapeutic purposes. Numerous PSMA tracers have been recently developed. This review aims to provide an overview on the clinical influence of PSMA tracers in primary staging, biochemical recurrence (BCR) of PC and advanced, metastatic PC. Additionally, the use of PSMA tracers in systemic radioligand therapy (RLT) of metastatic castration-resistant prostate cancer (mCRPC), as well as non-prostatic specific uptake of PSMA tracers and the use of PSMA imaging to manage therapy have been described. A computerized search of the literature (PubMed) was conducted in order to find evidence on the role of PSMA tracers in the diagnosis and therapy of PC. PSMA positron-emission tomography/computed tomography (PET/CT) outperforms conventional imaging in the settings of primary PC, BCR and advanced PC. Especially in BCR of PC, PSMA PET/CT shows clinical value with significantly higher detection rates than standard modalities. The use of PSMA PET/CT resulted in a change of the therapeutic management in up to half of the cases. Regarding RLT, smaller studies were able to show positive clinical effects of 177Lu-labeled PSMA tracers without the occurrence of severe side effects. The currently available data clearly shows that PSMA targeting has a clinical impact on the diagnosis of PC, and that RLT using radiolabeled PSMA tracers has high potentiality in the settings of resistance to conventional therapeutic approaches.