(UroToday.com) The European Society of Medical Oncology (ESMO) 2021 annual meeting’s prostate cancer session included a presentation by Dr. Stephen Freedland discussing treatment patterns and overall survival among men with metastatic castration-sensitive prostate cancer (mCSPC). Indeed, androgen deprivation therapy (ADT) remains the backbone of therapy for mCSPC. While earlier studies (pre-2012) adding first-generation nonsteroidal antiandrogens to ADT failed to show consistent OS improvement, clinical trials since 2014 combining docetaxel or novel hormonal therapies to ADT have shown improved OS over ADT alone in this population, with even greater benefit seen than in metastatic castration-resistant prostate cancer (mCRPC) population.
The National Comprehensive Cancer Network (NCCN) treatment guidelines recommend ADT in combination with docetaxel or novel hormonal therapies (abiraterone, apalutamide, or enzalutamide) for patients with mCSPC. Long-term treatment with first-generation nonsteroidal antiandrogens in combination with ADT may also be used to achieve combined androgen blockade, although earlier studies have failed to show a consistent OS improvement, and current guidelines note that there is likely minimal added benefit of nonsteroidal antiandrogens. As such, real-world data on treatment patterns and outcomes in mCSPC after the introduction of docetaxel and novel hormonal therapies are limited. The aim of the current study was to evaluate the real-world treatment patterns and outcomes over time in patients with mCSPC, using data from the Veterans Health Administration.
Veterans Health Administration data were used to retrospectively study patient characteristics, practice patterns, and OS in men with mCSPC who initiated either ADT alone or ADT with nonsteroidal antiandrogens, docetaxel, or novel hormonal therapies from 2006 to 2019. Kaplan-Meier and Cox models were used to estimate OS in three cohorts representing the periods before (2006-2011) and after (2012-2014) novel hormonal therapy introduction in mCRPC and novel hormonal therapy/docetaxel in mCSPC (2015-2019), respectively.
There were 7,340 men with mCSPC included in this study of which 4,420 (60%) received ADT alone, 2,092 (29%) received ADT + nonsteroidal antiandrogens, 261 (4%) received ADT + docetaxel, and 567 (8%) received ADT + novel hormonal therapies. Over time the use of ADT alone and ADT + nonsteroidal antiandrogens for mCSPC declined, and the use of ADT + docetaxel and ADT + novel hormonal therapies increased, though they remained low:
As of 2019, less than one-third of the men with mCSPC received first-line ADT + docetaxel or ADT + novel hormonal therapies. Patient characteristics were similar over time, albeit with an increasing prevalence of node metastases. The use of novel hormonal therapies as first-line treatment for mCRPC increased, and the use of chemotherapy or other treatments without novel hormonal therapies decreased:
OS improved over time: compared to 2006-2011, the risk of death was reduced by 14% (HR 0.86, 95% CI 0.79-0.93; p<0.001) and 25% (HR 0.75, 95% CI 0.70-0.81; p<0.001) in 2012-2014 and 2015-2019, respectively:
Dr. Freedland concluded this presentation of real-world data assessing treatment patterns and survival among patients with mCSPC with the following take-home messages:
- OS improvement in men with mCSPC coincided with the introduction of novel hormonal therapies in mCRPC and docetaxel and novel hormonal therapies in mCSPC
- However, only 20% of patients with mCSPC received treatment intensification with docetaxel or novel hormonal therapies in the most recent time period (2015-2019), suggesting there is room for significant survival improvement in this population
Presented by: Stephen J. Freedland, MD, Division of Urology, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2021 European Society for Medical Oncology (ESMO) Annual Congress 2021, Thursday, Sep 16, 2021 – Tuesday, Sep 21, 2021.