Real-World Survival Improvements In Patients With Newly Diagnosed Metastatic Prostate Cancer Treated In The United States

48 Background: New drugs have become available for the treatment of metastatic prostate cancer (mPCa) during the last two decades. Here, we explored the clinical outcomes of de novo mPCa in 3 large cohorts of patients diagnosed in 3 treatment eras: pre-docetaxel 2000-2003 (T1), docetaxel 2004-2010 (T2) and new androgen-receptor signalling inhibitors (ARSi) + cabazitaxel 2011-2016 (T3). Methods: The USA Surveillance Epidemiology and End Results (SEER) Incidence Data were investigated using the SEER*Stat software. We used the Kaplan – Meier method, log-rank test, Cox regression, hazard ratio (HR) and confidence intervals (CI) to analyse overall survival (OS) and cancer-specific survival (CSS). The maximum follow-up time point was 5 years. Results: A total 34.034 patients with de novo mPCa were analysed for OS, of these 6.621 T1, 12.711 T2 and 14.702 T3. Median OS was 29 months (mo) [95% CI: 28.5-29.5], 28 mo [27.0-28.9], 28 mo [27.3-28.7] and 31 mo [30.2-31.8] in whole, T1, T2 and T3 cohorts, respectively. In the multivariable model, adjusted for age and race, T3 patients showed better OS compared to T1 and T2 patients (HR: 0,92 [95% CI: 0,88-0,95] and 0,92 [0,89 to 0,95], respectively, p<0.001). A total of 33.641 patients were analysed for CSS, of these 6.514 T1, 12.540 T2 and 14.587 T3. Median CSS was 36 mo [35.3-36.7], 34 mo [32.6-35.3], 34 mo [33.0-35.0] and 38 mo [36.9-39.1] in whole, T1, T2, T3 cohorts, respectively. T3 patients had better CSS compared to T1 and T2 patients (HR: 0,93 [0,89-0,97] and 0,92 [0,89 to 0,96], respectively, p<0.001). No difference in OS or CSS was found between T1 and T2 cohorts. Conclusions: The prognosis of patients with de novo mPCa remains poor, with a median CSS of 3 years and a 5-year CSS of 35%. Approximately 8% decrease in the risk of death was found in the era of ARSi and cabazitaxel. The recent intensification of therapy in metastatic hormone-sensitive setting might lead to better outcomes in the next years.[Table: see text]