Diagnostic performance of 18F-DCFPyL positron emission tomography/computed tomography for biochemically recurrent prostate cancer and change-of-management analysis

Lutetium-177 Labelled Anti-PSMA Monoclonal Antibody (Lu-TLX591) Therapy for Metastatic Prostate Cancer: Treatment Toxicity and Outcomes

INTRODUCTION

Whilst prostate cancer is the fourth most common cancer globally, effective therapies for patients with advanced disease are lacking. In recent years, interest in using theranostic agents to treat castrate-resistant prostate cancer (CRPC) and metastatic prostate cancer has emerged. Lu-TLX591 monoclonal antibody is a potential agent of significance; however, to date, reports on its toxicity and efficacy have been limited to small clinical trials in heavily pretreated patients. This retrospective study describes the real-world toxicity and efficacy profile of Lu-TLX591.

METHODS

Eighteen patients received Lu-TLX591 at two private oncology centres in Australia. Patients were eligible if they had CRPC or metastatic prostate cancer and prostate-specific membrane antigen (PSMA)-avid disease confirmed by PSMA-positron emission tomography (PET). Patients received two cycles of Lu-TLX591 monoclonal antibody (177 Lu-DOTA-rosopatamab) each dosed from 1.01-2.85 GBq, 14 days apart. Patient side effects, blood test results and radiology reports were recorded on the patient's electronic medical record (eMR).

RESULTS

Prominent side effects included fatigue (55.6%), anorexia (16.7%), nausea (11.1%), and transfusion reactions (11.1%). All-grade haematological toxicities included lymphopenia (61.1%), anaemia (22.2%), leukopenia (27.8%), neutropenia (27.8%), and thrombocytopenia (27.8%). Grade 4 toxicity included lymphopenia (6.7%) and thrombocytopenia (6.7%). Patients' prostate-specific antigen (PSA) responses were as follows; ≥ 30% PSA decline (27.8%), ≥ 50% PSA decline (11.4%) and any PSA decline (38.9%). Follow-up radiology revealed 54.5% stable disease, 45.4% disease progression and 9.1% disease regression.

CONCLUSION

Lu-TLX591 was safely administered at acceptable toxicity and its efficacy reflects previous clinical trials. Larger studies are required and are underway (NCT04786847; NCT05146973; NCT04876651) to determine Lu-TLX591 effectiveness amongst different prostate cancer populations and compare its efficacy against peptide-based radiopharmaceutical agents.

Effect of 18F-DCFPyL PET on changes in management of patients with prostate cancer: a systematic review and meta-analysis

Purpose

Prostate-specific membrane antigen (PSMA)-targeted imaging has gained increasing interest in its application in prostate cancer lesion detection. Compared with 68Galium (68Ga), 18Fluoride (18F)-labeled imaging agent has easier syntheses, lower price, and a longer half-time. 2-(3-{1-Carboxy-5-[(6-[18F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid positron emission tomography (18F-DCFPyL PET) has been recently approved by the U.S. Food and Drug Administration. Several studies have proven its superiority to conventional imaging techniques in detecting prostate cancer lesions. However, the impact of 18F-DCFPyL PET on the management of patients with prostate cancer is not well established. Thus, we performed a systematic review and meta-analysis of available data to evaluate the impact of 18F-DCFPyL PET on the management of patients with prostate cancer.

Methods

The PubMed, Embase, Scopus, and Cochrane databases were searched up to April 2024. Studies that reported the proportion of changes in management after 18F-DCFPyL PET was performed in patients with prostate cancer were included. The Grading of Recommendations Assessment, Development, and Evaluation system was used for the quality evaluation of the included studies. The proportion of changes in management was pooled using a random effects model. Meta-regression analyses were performed to assess the potential correlation between the PET positivity and management changes.

Results

Fourteen studies (3,078 patients with prostate cancer) were included in our review and analysis. The pooled percentage of management changes was 43.5% (95% confidence interval [CI]: 33-54%). In patients with biochemical recurrent and for primary staging, the pooled percentage was 50% (95% CI: 39-60%) and 22% (95% CI: 15-29%), respectively. In the meta-regression analyses, PET positivity was detected as a significant predictor of management change (p = 0.0023).

Conclusion

18F-DCFPyL PET significantly affects the management of patients with prostate cancer. Higher PET positivity rate significantly correlated with a higher proportion of management changes in patients with prostate cancer. However, more studies are still needed to confirm the important role of 18F-DCFPyL PET in the management of prostate cancer.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#myprospero, CRD42022339178.

Piflufolastat F 18: Diagnostic First Approval

Piflufolastat F 18 (PYLARIFY^®) is an ¹⁸F-labelled diagnostic imaging agent that has been developed by Progenics Pharmaceuticals Inc., a Lantheus company, for positron emission tomography (PET) that targets prostate-specific membrane antigen (PSMA). Piflufolastat F 18 was approved in the USA on 27 May 2021 for PET of PSMA positive lesions in men with prostate cancer with suspected metastasis who are candidates for initial definitive therapy or with suspected recurrence based on elevated serum prostate specific antigen (PSA) level. This article summarizes the milestones in the development of piflufolastat F 18 leading to this approval as a radioactive diagnostic agent in prostate cancer.

The Diagnostic Role of 18F-Choline, 18F-Fluciclovine and 18F-PSMA PET/CT in the Detection of Prostate Cancer With Biochemical Recurrence: A Meta-Analysis

Background

Diagnosing the biochemical recurrence (BCR) of prostate cancer (PCa) is a clinical challenge, and early detection of BCR can help patients receive optimal treatment. We conducted a meta-analysis to define the diagnostic accuracy of PET/CT using ¹⁸F-labeled choline, fluciclovine, and prostate-specific membrane antigen (PSMA) in patients with BCR.

Methods

Multiple databases were searched until March 30, 2021. We included studies investigating the diagnostic accuracy of ¹⁸F-choline, ¹⁸F-fluciclovine, and ¹⁸F-PSMA PET/CT in patients with BCR. The pooled sensitivity, specificity, and detection rate of ¹⁸F-labeled tracers were calculated with a random-effects model.

Results

A total of 46 studies met the included criteria; 17, 16, and 13 studies focused on ¹⁸F-choline, fluciclovine, and PSMA, respectively. The pooled sensitivities of ¹⁸F-choline and ¹⁸F-fluciclovine were 0.93 (95% CI, 0.85–0.98) and 0.80 (95% CI, 0.65–0.897), and the specificities were 0.91 (95% CI, 0.73–0.97) and 0.66 (95% CI, 0.50–0.79), respectively. The pooled detection rates of ¹⁸F-labeled choline, fluciclovine and PSMA were 66, 74, and 83%, respectively. Moreover, the detection rates of ¹⁸F-labeled choline, fluciclovine, and PSMA were 35, 23, and 58% for a PSA level less than 0.5 ng/ml; 41, 46, and 75% for a PSA level of 0.5–0.99 ng/ml; 62, 57, and 86% for a PSA level of 1.0–1.99 ng/ml; 80, 92, and 94% for a PSA level more than 2.0 ng/ml.

Conclusion

These three ¹⁸F-labeled tracers are promising for detecting BCR in prostate cancer patients, with ¹⁸F-choline showing superior diagnostic accuracy. In addition, the much higher detection rates of ¹⁸F-PSMA showed its superiority over other tracers, particularly in low PSA levels.

Systematic Review Registration

PROSPERO, identifier CRD42020212531.