Korean J Radiol.  2018 Oct;19(5):819-831. 10.3348/kjr.2018.19.5.819.

Prostate-Specific Membrane Antigen PET Imaging in Prostate Cancer: Opportunities and Challenges

• Oh SW
• Cheon GJ

• KMID: 2418544
• DOI: http://doi.org/10.3348/kjr.2018.19.5.819

Abstract

The aim of this systematic review was to describe the characteristics of prostate-specific membrane antigen (PSMA)-targeting PET and their clinical applications in prostate cancer patients. There have been major strides in the design, synthesis of PSMA-targeting PET tracers over the past several years. PSMA-targeting PET tracers can be categorized, according to positron emitters and targeting strategies for the PSMA. The majority of PSMA PET studies has been focused on patients with biochemical recurrence, but additional values of PSMA PET have also been investigated for use in primary staging, treatment planning, response evaluation, and PSMA radioligand therapy. PSMA PET is expected to bring improvements in the management of patients, but the impact of improved diagnosis by PSMA on overall survival remains unanswered. Many challenges still await PSMA PET to expedite the use in the clinical practice. At this early stage, prospective multicenter trials are needed to validate the effectiveness and usefulness of PSMA PET.

Keyword

Prostate cancer; Prostate-specific membrane antigen; Prostate-specific PET tracers; PET/MRI; Recurrence

MeSH Terms

Diagnosis
Electrons
Humans
Membranes*
Multicenter Studies as Topic
Prospective Studies
Prostate*
Prostatic Neoplasms*
Recurrence

Figure

• 

  Fig. 1 Representative images of PSMA PET. A. 68Ga-PSMA-11 PET shows normal biodistribution of PSMA across body; lacrimal and salivary glands, liver, spleen, kidneys, and intestines. B. 18F-DCFPyL PET demonstrates normal biodistribution of PSMA which is similar to 68Ga-PSMA-11 PET with better image resolution. These images were reprinted with permissions from reference articles 28 and 81, respectively. Adapted from Fendler et al. Eur J Nucle Med Mol Imaging 2017;44:1014-1024, 2017;44:2117-2136 [28] and Sheikhbahaei et al. Eur J Nucle Med Mol Imaging 2017;44:2117-2136 [81], with permissions of Springer Science and Bus Media B V. PSMA = prostate-specific membrane antigen

• 

  Fig. 2 PSA level and 68Ga-PSMA PET positivity. Scatterplot shows association between PSA level and 68Ga-PSMA PET positivity. Red line is meta-regression prediction and shading shows 95% confidence interval. Size of circles is related to inverse of variance. This image was reprinted with permission from reference article 42. Adapted from Perera et al. Eur Urol 2016;70:926-937, with permission of Elsevier Science and Technology Journals [42]. PSA = prostate specific antigen

• 

  Fig. 3 Potential benefits of PSMA PET for treatment planning. 68Ga-PSMA-I&T PET/CT was performed in prostate cancer patient (Gleason Scores 4 + 5 = 9) who planned external beam radiation therapy after radical prostatectomy 1 month ago, and PSA level was 0.37 ng/mL at time of PET scanning. Maximum intensity projection shows multiple uptakes (arrows) suggestive of metastases (A), and axial fusion PET/CT images demonstrate metastatic retroperitoneal lymph nodes (arrows) with diameters of 3 mm (B) and 9 mm (C). These images were provided by courtesy of Professor Dr. Richard P. Baum at THERANOSTICS Center for Molecular Radiotherapy & Molecular Imaging, Zentralklinik Bad Berka, Germany.

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