Rates of PSMA PET Staging and Positivity in Newly Diagnosed Prostate Cancer in a National Health Care System

Abstract

Prostate-specific membrane antigen (PSMA) PET was approved by the U.S. Food and Drug Administration in 2020 for the staging of newly diagnosed prostate cancer, yet rates of adoption and real-world positivity rates are unknown. We characterized patients undergoing PSMA PET staging and describe positive findings in a large national cohort. <b>Methods:</b> We identified all newly diagnosed prostate cancer patients in the national Veterans Health Administration from June 2020 to August 2023. Demographics, staging imaging reports, and cancer-related information were obtained from electronic medical record data. To assess positive findings, we chart-reviewed 1,994 patients (<i>n</i> = 657 low to intermediate risk) with staging PSMA PET reports available. <b>Results:</b> Among 31,838 patients with newly diagnosed prostate cancer, 4,538 (14%) underwent PSMA staging. Use of PSMA staging increased rapidly from near 0 in early 2021 to approximately 70% of patients with high- or very-high-risk disease by August 2023. Among patients who were N0/M0 by conventional imaging, PSMA PET positivity rates (N1 or M1) were 5.9% for favorable intermediate risk, 8.2% for unfavorable intermediate risk, 14% for high risk, and 34% for very high risk. <b>Conclusion:</b> PSMA PET staging for newly diagnosed prostate cancer increased rapidly in the Veterans Health Administration. Positivity rates were less than 10% in this large intermediate-risk cohort. These data confirm the utility of PSMA PET staging in high-risk disease and suggest that additional study is needed to refine patient selection in intermediate-risk disease.