“Seeing Is Believing”: Additive Utility of [sup.68]Ga-PSMA-11 PET/CT in Prostate Cancer Diagnosis

This study investigates the effectiveness of combining two imaging techniques, multiparametric magnetic resonance imaging (mpMRI) and [sup.68]Ga-Prostate-specific membrane antigen (PSMA-11) positron emission tomography/computed tomography (PET/CT), to diagnose clinically significant prostate cancer (csPCa). While mpMRI is commonly used, it has limitations in its accuracy, requires further confirmation with prostatic biopsy. This study explores whether adding [sup.68]Ga-PSMA-11 PET/CT enhances diagnostic accuracy. The results show that the combined approach significantly improves the detection of csPCa compared to using either modality alone. Specifically, when both imaging methods are able to detect suspicious lesions, the likelihood of csPCa is high. This study suggests that, in select cases with convincing imaging results, it may be possible to forgo biopsy before surgical treatment. However, further research is needed to validate these findings and develop predictive models for accurate diagnosis without biopsy. Widespread adoption of mpMRI has led to a decrease in the number of patients requiring prostate biopsies. [sup.68]Ga-PSMA-11 PET/CT has demonstrated added benefits in identifying csPCa. Integrating the use of these imaging techniques may hold promise for predicting the presence of csPCa without invasive biopsy. A retrospective analysis of 42 consecutive patients who underwent mpMRI, [sup.68]Ga-PSMA-11 PET/CT, prostatic biopsy, and radical prostatectomy (RP) was carried out. A lesion-based model (n = 122) using prostatectomy histopathology as reference standard was used to analyze the accuracy of [sup.68]Ga-PSMA-11 PET/CT, mpMRI alone, and both in combination to identify ISUP-grade group ≥ 2 lesions. [sup.68]Ga-PSMA-11 PET/CT demonstrated greater specificity and positive predictive value (PPV), with values of 73.3% (vs. 40.0%) and 90.1% (vs. 82.2%), while the mpMRI Prostate Imaging Reporting and Data System (PI-RADS) 4–5 had better sensitivity and negative predictive value (NPV): 90.2% (vs. 78.5%) and 57.1% (vs. 52.4%), respectively. When used in combination, the sensitivity, specificity, PPV, and NPV were 74.2%, 83.3%, 93.2%, and 51.0%, respectively. Subgroup analysis of PI-RADS 3, 4, and 5 lesions was carried out. For PI-RADS 3 lesions, [sup.68]Ga-PSMA-11 PET/CT demonstrated a NPV of 77.8%. For PI-RADS 4–5 lesions, [sup.68]Ga-PSMA-11 PET/CT achieved PPV values of 82.1% and 100%, respectively, with an NPV of 100% in PI-RADS 5 lesions. A combinat