Despite the introduction of ADT intensification for metastatic hormone-sensitive prostate cancer (mHSPC) in 2015, the use of these therapies remains limited in Asia. Therefore, we wish to report real-life data on de novo mHSPC and the utilization and efficacy of upfront therapy results in our region.

The study utilized data from an established prospective database that included information from five regional urological centres in Hong Kong since 2016. Patients diagnosed with de novo mHSPC from January 2016 to December 2023 were identified, and their data was retrieved from electronic hospital records. ADT intensification was defined as initiating first-line chemotherapy or ARPI within six months of commencing ADT. High-volume and high-risk diseases were defined according to the CHARTEED trial and LATITUDE criteria.

Between 2016 and 2023, 814 patients (24.6%) with mHSPC were identified. The median age at diagnosis was 72 years (67-78). The median follow-up period was 40 months (IQR 25-57), and 76.8% of patients had ISUP Grade 4/5 diseases. At diagnosis, the median PSA level was 144(49-537) ng/ml. Among these patients, 481 (59.1%) were classified as high volume, and 438 (53.8%) as high risk, respectively. ADT monotherapy remained the most common primary treatment (52.0%) across the entire cohort. Only 234 patients (28.7%) underwent ADT intensification treatment. Among these patients, 167 (20.5%) received upfront docetaxel chemotherapy, 48 (5.9%) were treated with abiraterone and prednisolone, 9 (1.1%) with enzalutamide, and 10 (1.2%) with apalutamide. 490 (60.2%) patients progressed to castration-resistant prostate cancer (CRPC). The median time from ADT, whether with or without intensification, to CRPC was 19 months (17-21). During the study period, 394 patients (48.4%) died, with 307 (77.9%) deaths attributed to PCa. The 5-year CRPC-free rate, 5-year overall survival (OS), and 5-year cancer-specific survival (CSS) for ADT monotherapy, ADT with upfront chemotherapy and ADT with upfront androgen receptor pathway inhibitor (ARPI) are listed in Table 1. A trend of superiority for ARPI over chemotherapy was also observed in both overall and also high volume disease patients. Multivariable Cox regression analysis showed that high-volume disease and initial treatment were significantly correlated with both OS and CSS.

Despite the underutilization of ADT intensification in mHSPC patients, our real-world data supports its role in prolonging overall and cancer-specific survival. Disclosure: This study was supported by Astellas Pharma, Inc.