Cost-Effectiveness Analysis of Prostate-Specific Membrane Antigen (PSMA) Positron Emission Tomography/Computed Tomography (PET/CT) for the Primary Staging of Prostate Cancer in Australia

Abstract

BACKGROUND AND OBJECTIVES: Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) combined with computed tomography (CT) is a new imaging modality to detect the extra-prostatic spread of prostate cancer. PSMA PET/CT has a higher sensitivity and specificity than conventional imaging (CT ± whole body bone scan [WBBS]). This study conducted a cost-utility analysis of PSMA PET/CT compared with conventional imaging for patients with newly diagnosed, intermediate-risk or high-risk primary prostate cancer. PERSPECTIVE: Australian healthcare perspective. SETTING: Tertiary. METHODS: A decision-analytic Markov model combined data from a variety of sources. The time horizon was 35 years. The sensitivity and specificity of PSMA PET/CT and CT alone were based on meta-analyses and the test accuracy of CT+WBBS was based on a single randomised controlled trial. Health outcomes included cases detected, life-years, and quality-adjusted life-years. Costs related to other diagnostic tests, initial treatment, adverse events, and post-disease progression were included. All costs were reported in 2021 Australian Dollars (A$). RESULTS: The deterministic incremental cost-effectiveness ratio of PSMA PET/CT was estimated to be A $21,147/quality-adjusted life-year gained versus CT+WBBS, and A$36,231/quality-adjusted life-year gained versus CT alone. The results were most sensitive to the time horizon, and the initial treatments received by patients diagnosed with metastatic cancer. The probability of PSMA PET/CT being cost effective was estimated to be 91% versus CT+WBBS and 89% versus CT alone, using a threshold of AU$50,000/quality-adjusted life-year gained. CONCLUSIONS: PSMA PET/CT is likely to be more costly than CT+WBBS or CT alone in Australia; however, it is still likely to be considered cost effective compared with conventional imaging.