Background: Upfront docetaxel or novel hormonal agents (NHA) such as abiraterone and enzalutamide have become the standard of care for metastatic hormone sensitive prostate cancer (mHSPC). However, data comparing the efficacy of docetaxel and NHAs in this setting are limited.
Patients and Methods: This was a retrospective cohort study of patients with de novo mHSPC treated with upfront docetaxel or an NHA between January 1, 2014 and April 30, 2019 within the Mount Sinai Health System. Clinical data were extracted from the medical record. The primary outcome was failure-free survival (FFS), defined as the time to next treatment. The primary predictor was treatment with docetaxel or NHA. FFS was compared between the two groups using the Kaplan Meier method and multivariable Cox proportional hazards models. We additionally assessed the prognostic value of post-treatment PSA.
Results: We identified 94 de novo mHSPC patients; 52 and 42 treated with upfront docetaxel and NHAs, respectively. NHAs were associated with significantly longer FFS compared to docetaxel (20.7 vs. 10.1 months, p=0.023). In a multivariable model adjusting for demographics and clinical factors, docetaxel was independently associated with worse FFS compared to NHAs (HR 1.96, 95% CI 1.12−3.45, p=0.019). High metastasis burden patients had a significantly longer FFS with NHAs than docetaxel (25.12 vs. 9.63 months, p=0.014), while there was no significant difference in FFS among low metastasis burden patients (NHA 20.71 vs. Docetaxel 26.5 months, p=0.9). Regardless of treatment, lower post-treatment PSA levels were associated with improved FFS (58.95 vs. 11.57 vs. 9.4 months for PSA ≤0.2, 0.2-0.4, >0.4ng/ml, respectively; p<0.001)
Conclusion: Comparative analysis of real-world data demonstrated longer FFS in de novo mHSPC treated with NHA compared to docetaxel. In addition, the depth of PSA response following combination treatment may hold prognostic value for mHSPC outcomes.