前立腺がん患者における高リスク生化学的再発例に対するPSMA-PETイメージング：「EMBARK」類似コホートからの示唆

The EMBARK trial demonstrated improved survival with enzalutamide plus androgen deprivation therapy (ADT) in non-metastatic hormone-sensitive prostate cancer patients with high-risk biochemical recurrence (BCR), although staged using conventional imaging. Given the higher sensitivity of PSMA-PET, many of these patients could harbor metastatic disease. We retrospectively analyzed 587 patients with first BCR after radical treatment who underwent PSMA-PET. Patients were stratified according to EMBARK criteria for high-risk BCR. 169 patients (29%) met EMBARK criteria. They more often showed PSMA-PET positivity for any localization (82% vs 39%; p < 0.001) and metastatic disease (46% vs 15%; p < 0.001). Median PSA was higher and PSA doubling-time (PSADT) shorter (2.23 vs 0.43 ng/mL; 4.3 vs 9 months). Most High-risk BCR patients have a positive PSMA-PET, and many of these harbor metastatic disease at molecular imaging. Given the survival benefit from intensified systemic treatment with ARPI in this cohort, how to best combine systemic therapy with PSMA-PET guided metastases-directed-treatments remains an important future area of research.