Changes in the treatment landscape of metastatic hormone-sensitive prostate cancer: A multicenter study.

118 Background: A multicenter database was utilized to examine the current treatment landscape and clinical outcomes among patients with metastatic hormone-sensitive prostate cancer (mHSPC) following approval of upfront androgen receptor signaling inhibitors (ARSIs). Methods: We retrospectively analyzed patients with mHSPC who commenced treatment between February 2018 and June 2023. The Kaplan–Meier method was used to assess oncological outcomes, including time to castration-resistant prostate cancer (CRPC), progression-free survival 2 (PFS2, duration from initial treatment to tumor progression during second-line treatment), cancer-specific survival (CSS), and overall survival (OS). Cox regression analyses were performed to determine the impact of treatment choices on oncological outcomes. In addition, the incidence rate of adverse events was assessed. Results: In total, 829 patients were analyzed; 42.5% received ARSIs with androgen deprivation therapy (ADT), 44.0% received combined androgen blockade (CAB), and 13.5% received ADT alone. Analysis of annual treatment choice trends revealed an increasing preference for ARSIs with ADT. Kaplan–Meier curves and multivariate Cox regression analyses indicated higher rates of CRPC and shorter PFS2 in patients treated with CAB versus ARSIs with ADT. By contrast, CSS and OS were not significantly different between the ARSI with ADT group and the CAB group. Grade 3–4 adverse events occurred in 1.9% of patients receiving CAB and 6.0% of those receiving ARSIs with ADT. Conclusions: For patients with mHSPC, initial treatment with ARSIs in combination with ADT resulted in a longer time to CRPC and longer PFS2 compared to CAB. Although CAB and ADT alone were associated with fewer adverse events, ARSIs with ADT should be considered a first-line treatment option given its superior oncological outcomes.