Introduction:

Patients (pts) with high-risk localized prostate cancer (LPC) or locally advanced prostate cancer (LAPC) have several treatment options, including external beam radiation therapy (EBRT) or radical prostatectomy (RP). While these treatments can be curative in some pts, limited real-world evidence exists on their long-term clinical outcomes stratified by race/ethnicity. This study examines real-world clinical outcomes for pts with high-risk LPC or LAPC (HR-LPC) treated with either EBRT or RP by race/ethnicity.

Methods:

A retrospective cohort study was conducted using Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data. Patients newly diagnosed with HR-LPC at age ≥65 between 2012 and 2017 with available race/ethnicity status that received RP or EBRT as initial definitive therapy (index date) within 6-months of initial diagnosis were included. LPC risk classification was determined per NCCN criteria. Race/ethnicity status were identified as Non-Hispanic [NH] White, NH Black, NH Asian, and Hispanic. Baseline sociodemographic and clinical characteristics were summarized during a 12-month period prior to the index date. Clinical outcomes (overall survival [OS], metastasis-free survival [MFS] and time to advanced prostate cancer [PC] treatment) were assessed via Kaplan-Meier (KM). All analyses were stratified by the race/ethnicity status and initial definitive treatment.

Results:

Of 7,774 pts diagnosed with HR-LPC, 58% (N=4,475) and 42% (N=3,299) initiated EBRT and RP as their initial definitive therapy within 6 months of diagnosis, respectively. Patient race/ethnicity were as follows: 86% NH White, 6% NH Black, 4% NH Asian, and 4% Hispanic. Patient characteristics appeared similar across race/ethnicity groups, with mean ages at treatment initiation of 74 years for EBRT and 70 years for RP and mean follow-up time of around 40-45 months. Within 5 years after initial definitive treatment initiation, approximately 30% of patients with HR-LPC treated with EBRT or RP are estimated to have died or reached metastasis (rising to nearly 40% among Black patients treated with RP). Moreover, Black patients treated with RP faced two-fold higher likelihood of death as compared to White patients and also appeared less likely to initiate advanced PC treatment despite exhibiting lower MFS within 5 years relative to other patients.

Conclusion:

This real-world study of clinical outcomes in pts with HR-LPC treated with EBRT or RP as their initial definitive therapy suggests substantial rates of 5-year progression to metastasis or death across race and ethnicity, particularly for Black patients treated with RP. These results highlight the need for additional strategies and treatments to improve clinical outcomes in pts with HR-LPC.

Funding: Study sponsored by: Janssen Scientific Affairs, LLC