Dual-Tracer Positron-Emission Tomography Using Prostate-Specific Membrane Antigen and Fluorodeoxyglucose for Staging of Prostate Cancer: A Systematic Review.

Stephen Mcgeorge,David A Pattison,Andrew Jiang,John W Yaxley,Paul A Thomas,Louise Emmett,Matthew J Roberts,Michael Kwok,Mohammad H Ather

doi:10.1155/2021/1544208

Abstract

PSMA PET is more accurate than conventional imaging (CT/bone scan) for staging of intermediate- or high-risk prostate cancer (PCa), but 5–10% of primary tumours have low PSMA ligand uptake. FDG PET has been used to further define disease extent in end-stage castrate-resistant PCa and may be beneficial earlier in the disease course for more accurate staging. The objective of this study was to review the available evidence for patients undergoing both FDG and PSMA PET for PCa staging at initial diagnosis and in recurrent disease. A systematic literature review was performed for studies with direct, intraindividual comparison of PSMA and FDG PET for staging of PCa. Assessment for radioligand therapy eligibility was not considered. Risk of bias was assessed. 543 citations were screened and assessed. 13 case reports, three retrospective studies, and one prospective study were included. FDG after PSMA PET improved the detection of metastases from 65% to 73% in high-risk early castration-resistant PCa with negative conventional imaging (M0). Positive FDG PET was found in 17% of men with negative PSMA PET for postprostatectomy biochemical recurrence. Gleason score ≥8 and higher PSA levels predicted FDG-avid metastases in BCR and primary staging. Variant histology (ductal and neuroendocrine) was common in case reports, resulting in PSMA-negative FDG-positive imaging for 3 patients. Dual-tracer PET for PCa may assist in characterising high-risk disease during primary staging and restaging. Further studies are required to determine the additive benefit of FDG PET and if the FDG-positive phenotype may indicate a poorer prognosis.

Highlights

Prostate cancer (PCa) is the most commonly diagnosed internal malignancy and high-ranking cause of mortality in men worldwide [1, 2]
We sought to summarise the available evidence for the use of dual-tracer positron-emission tomography (PET), being 18-F-fluorodeoxyglucose (FDG) PET in addition to prostate-specific membrane antigen (PSMA) PET, for PCa staging at initial diagnosis and in recurrent disease
A prospective single-arm trial investigated the prevalence of PSMA-negative FDGpositive lesions in 37 men with negative conventional imaging (M0) in the setting of high-risk early castration resistance who were restaged using PSMA and FDG PET [33]. 65% of men had metastatic disease on initial PSMA PET, while an additional 5% had localised PSMA avidity within the prostate, which was concordant with FDG PET

Summary

Introduction

Prostate cancer (PCa) is the most commonly diagnosed internal malignancy and high-ranking cause of mortality in men worldwide [1, 2]. 18-F-Fluorodeoxyglucose (FDG) PET use in PCa has previously been of limited benefit in primary staging and biochemical recurrence (BCR) [19, 20]. Increasing use of FDG PET to aid patient selection for RLT and other therapies in mCRPCa has provided insight into tumour heterogeneity and benefits of dual-tracer PET imaging [22, 23]. Additional use of FDG PET may improve disease characterisation in patients with high-risk localised and metastatic PCa, with inconclusive conventional imaging and negative PSMA PET. We sought to summarise the available evidence for the use of dual-tracer PET, being 18-F-fluorodeoxyglucose (FDG) PET in addition to PSMA PET, for PCa staging at initial diagnosis and in recurrent disease

Methods

Findings

37 Not documented

Disclosure