The Role of [68Ga]PSMA PET/CT for Clinical Suspicion of Prostate Cancer in Patients with or without Previous Negative Biopsy: A Systematic Review

Abstract

The purpose of the study is to systematically evaluate the evidence regarding the role of [68Ga]PSMA PET/CT for clinical suspicions of prostate cancer in patients with or without previous negative biopsy. We performed a critical review of PubMed and Web of Science according to the PRISMA statement. Eighteen publications were selected for inclusion in this analysis. QUADAS-2 evaluation was adopted for quality analyses. [68Ga]PSMA-11 was the radiotracer of choice in 15 studies, while [68Ga]PSMA-617 was used in another 3. In 8 articles, there was a direct comparison with mpMRI. The total number of patients included was 1379, ranging from 15 to 291, with a median age of 64 years (range: 42–90). The median baseline PSA value was 12.9 ng/mL, ranging from 0.85 to 4156 ng/mL. Some studies evaluated the PSMA uptake comparing the SUVmax of suspicious lesions with the SUVmax of the normal biodistribution to find out optimal cut-off points. In addition, some studies suggested a significant association between PSA levels, PSA density, and [68Ga]PSMA PET/CT finding. [68Ga]PSMA PET/CT seems to be more accurate in identifying primary prostate cancer with PSA values between 4 and 20 ng/mL than mpMRI. Moreover, in some trials, the combination of PSMA PET/CT and MRI improved the NPV in the detection of clinically significant prostate cancer (csPCa) than MRI alone. Our findings are limited by the small numbers of studies and patient heterogeneity. [68Ga]PSMA PET/CT is a promising technique in patients with clinical suspicion of PCa and precedent negative biopsy or contraindications to MRI. Furthermore, its use combined with MRI improves sensitivity for csPCa detection and can avoid unnecessary biopsies.

Updates in the Treatment of Non-Metastatic Castrate-Resistant Prostate Cancer: The Benefit of Second-Generation Androgen Receptor Antagonists

“…46 The PSMA PET scans are much more sensitive at identifying small-volume disease, although 10% to 15% patients undergoing this imaging modality will be PSMA-negative. 47 The use of these more sensitive imaging modalities may identify more patients with metastatic CRPC earlier and thus the MFS times that we’ve observed with second-generation AR antagonists in the treatment M0CRPC may not be as robust. Currently, the NCCN guidelines recommend bone imaging with technetium-99-m-MDP bone scan, and soft tissue imaging of the pelvis, abdomen, and chest with chest CT and abdominal/pelvis CT or abdominal/pelvis MRI.…”

Staging Prostate Cancer with68Ga-PSMA-11 PET/CT in the Elderly: Is Preimaging Biopsy Imperative?

“…Of the 100 patients, 34 (34%) were referred for 68 Ga-PSMA-11 PET/CT on the basis of high clinical suspicion only, without preimaging histopathologic confirmation of PCa (Table 2. Eighteen (53%) of these 34 were referred after documentation of significantly elevated PSA levels (.50 ng/mL), 15 (44.1%) were referred because of prominent clinical symptoms (11 had urinary symptoms, 4 had bone pain), and 1 (2.8%) was referred because of focal prostatic 18 F-FDG uptake observed on 18 F-FDG PET/CT performed for colon cancer follow-up. Among these 34 B(2) patients, 10 (29.4%) underwent prostate MRI before referral for PSMA PET/CT, with the highest reported Prostate Imaging-Reporting and Data System score (4 or 5) documented in 9 of them.…”

Histology and PSMA Expression on Immunohistochemistry in High-Risk Prostate Cancer Patients: Comparison with 68Ga-PSMA PET/CT Features in Primary Staging

“…As demonstrated by a ProPSMA study [ 3 ], PSMA-PET/CT is a suitable replacement for conventional imaging, providing superior accuracy to the combined findings of CT and bone scanning in staging. In combination with an MRI, it improves the detection of primary PCa, avoiding unnecessary biopsies; it also seems to be more accurate in identifying PCa in patients with an iPSA > 4 ng/dL than an mpMRI alone [ 4 ]. Furthermore, it is a promising tool in patients with suspected PCa and a negative biopsy [ 4 ].…”

“…In combination with an MRI, it improves the detection of primary PCa, avoiding unnecessary biopsies; it also seems to be more accurate in identifying PCa in patients with an iPSA > 4 ng/dL than an mpMRI alone [ 4 ]. Furthermore, it is a promising tool in patients with suspected PCa and a negative biopsy [ 4 ]. Moreover, the use of PSMA-PET/CT leads to a change in clinical management in approximately 28% of cases in primary staging [ 3 ] and 50% of cases in restaging [ 5 , 6 ].…”