Rowe S P, Gorin M A, Allaf M E, Pienta K J, Tran P T, Pomper M G, Ross A E, Cho S Y
The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
The James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Prostate Cancer Prostatic Dis. 2016 Sep;19(3):223-30. doi: 10.1038/pcan.2016.13. Epub 2016 May 3.
Prostate-specific membrane antigen (PSMA) is a cell surface enzyme that is highly expressed in prostate cancer (PCa) and is currently being extensively explored as a promising target for molecular imaging in a variety of clinical contexts. Novel antibody and small-molecule PSMA radiotracers labeled with a variety of radionuclides for positron emission tomography (PET) imaging applications have been developed and explored in recent studies.
A great deal of progress has been made in defining the clinical utility of this class of PET agents through predominantly small and retrospective clinical studies. The most compelling data to date has been in the setting of biochemically recurrent PCa, where PSMA-targeted radiotracers have been found to be superior to conventional imaging and other molecular imaging agents for the detection of locally recurrent and metastatic PCa.
Early data, however, suggest that initial lymph node staging before definitive therapy in high-risk primary PCa patients may be limited, although intraoperative guidance may still hold promise. Other examples of potential promising applications for PSMA PET imaging include non-invasive characterization of primary PCa, staging and treatment planning for PSMA-targeted radiotherapeutics, and guidance of focal therapy for oligometastatic disease.
However, all of these indications and applications for PCa PSMA PET imaging are still lacking and require large, prospective, systematic clinical trials for validation. Such validation trials are needed and hopefully will be forthcoming as the fields of molecular imaging, urology, radiation oncology and medical oncology continue to define and refine the utility of PSMA-targeted PET imaging to improve the management of PCa patients.
前列腺特异性膜抗原（PSMA）是一种细胞表面酶，在前列腺癌（PCa）中高度表达，目前在各种临床环境中作为分子成像的一个有前景的靶点正在被广泛探索。近年来，已开发并研究了用多种放射性核素标记的新型抗体和小分子PSMA放射性示踪剂用于正电子发射断层扫描（PET）成像应用。
通过主要是小型回顾性临床研究，在确定这类PET药物的临床应用价值方面已经取得了很大进展。迄今为止，最有说服力的数据来自生化复发的PCa患者，在这类患者中，已发现PSMA靶向放射性示踪剂在检测局部复发和转移性PCa方面优于传统成像和其他分子成像药物。
然而，早期数据表明，高危原发性PCa患者在确定性治疗前的初始淋巴结分期可能有限，尽管术中引导可能仍有前景。PSMA PET成像潜在的有前景的应用的其他例子包括原发性PCa的非侵入性特征描述、PSMA靶向放射治疗的分期和治疗计划，以及寡转移疾病的局部治疗引导。
然而，PCa的PSMA PET成像的所有这些适应症和应用仍然缺乏验证，需要大型、前瞻性、系统性临床试验。随着分子成像、泌尿外科、放射肿瘤学和医学肿瘤学领域继续定义和完善PSMA靶向PET成像的应用价值以改善PCa患者的管理，这样的验证试验是必要的，有望很快开展。
