Abstract
INTRODUCTION: Prostate-Specific Membrane Antigen Positron Emission Tomography Computed Tomography (PSMA PET/CT) has shown a higher diagnostic accuracy in prostate cancer imaging when compared to conventional modalities, with improved sensitivity and specificity rates when combined with multiparametric prostate Magnetic Resonance Imaging (mpMRI). We evaluated the cost-effectiveness of a combined PSMA PET/CT and mpMRI biopsy-free diagnostic approach for clinically significant prostate cancer (csPCa). METHOD: A decision tree model was designed to compare two diagnostic strategies for csPCa in men with raised Prostate Specific Antigen (PSA)-the first with conventional mpMRI followed by transperineal prostate biopsy versus a second biopsy-free, PSMA PET/CT plus mpMRI combined imaging strategy. We evaluated the impact of each strategy on costs and Quality-Adjusted-Life-Years (QALYs). Willingness-to-pay thresholds were set at 1× and 3× Gross Domestic Product (GDP). One-way sensitivity analysis and probabilistic sensitivity analyses were performed. RESULTS: A combined mpMRI and PSMA PET/CT diagnostic strategy was 0.04 QALY more effective but SGD$4088.03 more expensive than the conventional mpMRI and biopsy strategy. The incremental cost-effective ratio (ICER) was SGD$92782.87 per quality-adjusted life year (QALY). In the combined imaging strategy, 3.5% of the cohort had a missed diagnosis of prostate cancer versus 13.9% in the conventional mpMRI and biopsy strategy. Probabilistic analyses showed that the combined imaging strategy was cost-effective at willingness-to-pay thresholds of SGD$121160 and SGD$363480, respectively. CONCLUSION: Combined mpMRI and PSMA PET/CT for csPCa diagnosis are a cost-effective strategy in terms of health utility over the conventional approach for diagnosing csPCa in men with raised PSA, potentially reducing the need for invasive diagnostic procedures.