An Audit of the Patterns of Prostate Carcinoma Metastases in Patients Referred for PSMA PET/CT Imaging at Charlotte Maxeke Johannesburg Academic Hospital

Abstract

INTRODUCTION: Prostate cancer (PCa) remains a significant global health concern, with accurate staging being key for effective management and prognostication. AIM: This study aimed to audit the findings from Prostate Specific Membrane Antigen (PSMA) PET/CT reports and describe the patterns of metastases in patients referred for initial staging at the Charlotte Maxeke Johannesburg Academic Hospital (CMJAH), while investigating associations between serum index Prostate Specific Antigen (iPSA) levels, Gleason Scores (GS), and disease burden. METHODOLOGY: A retrospective analysis was conducted on 108 PSMA PET/CT reports performed between January 2018 and December 2020. Patient data, including demographics, serum iPSA levels, GS, and PSMA-avid disease sites, were analyzed. RESULTS: The majority of patients (84.3%) had biopsy-confirmed adenocarcinoma, with 40.7% presenting with an iPSA ≥20 μg/L. Metastatic patterns included locoregional nodal disease (23.2%), distant nodal disease (12%), and distant organ involvement (15.7%), primarily in bone (88.2%). Statistically significant findings included the association of locoregional (p=0.002) and distant nodal disease (p=0.013) in high-risk patients, and extra-pelvic nodal involvement with iPSA >20 μg/L (p=0.018). Higher GS (≥8) was significantly linked to locoregional (p<0.001) and distant nodal metastases (p=0.001). CONCLUSIONS: These findings demonstrate the utility of PSMA PET/CT in the staging of all 3 risk categories of PCa, providing evidence for its role in guiding personalized treatment approaches.