Diagnostic Accuracy of PSMA-targeted 18F-Florastamin PET/CT in Intermediate-risk Patients With Suspected Prostate Cancer.

Purpose: This study aimed to evaluate the diagnostic accuracy of 18F-Florastamin prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET/CT) in detecting intermediate-risk prostate cancer and compare its performance with multiparametric magnetic resonance imaging (mpMRI).

Patients and methods: Fifty-nine patients with suspected intermediate-risk prostate cancer (prostate-specific antigen: 3-20 ng/mL) were prospectively enrolled. All participants underwent examination with 18F-Florastamin PET/CT and mpMRI, with imaging results assessed using the PSMA-Reporting and Data System and Prostate Imaging-Reporting and Data System Version 2.1 scoring systems, respectively. Prostate biopsy served as the reference standard. Diagnostic metrics, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver operating characteristic curve (AUC), were calculated to compare the 2 modalities.

Results: PSMA PET/CT demonstrated a sensitivity of 72.4%, specificity of 83.3%, and overall accuracy of 78%, with an AUC of 0.78 (95% CI: 0.67-0.89). Contrastingly, mpMRI showed a higher sensitivity (89.7%) but lower specificity (66.7%), achieving the same overall accuracy of 78% and an AUC of 0.78 (95% CI: 0.68-0.88). No statistically significant difference in AUC was observed between the 2 modalities (P=0.967). While PSMA PET/CT offered higher specificity and PPV, reducing false-positive results, mpMRI excelled in sensitivity and NPV, minimizing false negatives.

Conclusions: 18F-Florastamin PSMA PET/CT demonstrated comparable diagnostic accuracy to mpMRI, with the added benefit of higher specificity. These findings suggest that PSMA PET/CT could complement mpMRI in the diagnostic evaluation of intermediate-risk prostate cancer, enhancing patient stratification and aiding clinical decision-making.