(UroToday.com) The European Society of Medical Oncology (ESMO) 2021 virtual annual meeting’s prostate cancer session included a presentation by Dr. Daniel George presenting data assessing real-world utilization of advanced therapies by metastatic site and age among patients with metastatic castration-sensitive prostate cancer (mCSPC). ADT remains the backbone of therapy for mCSPC, however randomized trials have shown that adding docetaxel or novel hormonal therapy to androgen deprivation therapy (ADT) improves survival in mCSPC. The National Comprehensive Cancer Network treatment guidelines recommend ADT in combination with docetaxel or novel hormone therapy (abiraterone, apalutamide, and enzalutamide) for patients with mCSPC. Additionally, real-world data on treatment distribution and clinical outcomes in mCSPC after docetaxel and novel hormone therapy introduction are limited. This study using the Medicare database (Jan 2009–Dec 2018) aimed to evaluate real-world utilization of advanced therapies for men with mCSPC over time by metastatic site and age.
The analysis included adult men with ≥1 prostate cancer claim who initiated ADT (index date) ≤90 days prior to or any time after a metastasis diagnosis. First-line treatment was grouped in 4 categories: ADT only, ADT + nonsteroidal antiandrogen (≥90-day use), ADT + docetaxel, and ADT + novel hormonal therapy. The first-line treatment distributions were described over time by metastatic site and by patient age (<75 years versus ≥75 years) at index date. Kaplan-Meier curves and Cox (unadjusted) models were used to describe OS among patients with visceral metastasis and by age at treatment initiation.
Among the 35,209 men with mCSPC (mean age 76.5 years), 69.5% received ADT-only as first-line treatment, 24.0% received ADT + nonsteroidal antiandrogen, 3.5% received ADT + docetaxel, and 1,595 (3.0%) ADT + novel hormonal therapy. Most patients, including those with more aggressive disease (visceral metastases), were still treated with ADT alone or ADT + nonsteroidal antiandrogen even in the most recent period of 2017-2018:
After the emergence of docetaxel and novel hormonal therapy for mCSPC in 2014 and 2017, respectively, treatment intensification with ADT + docetaxel and ADT + novel hormonal therapy was numerically higher for patients with bone and/or visceral versus node-only metastases. However, the majority still received ADT-only or ADT + nonsteroidal antiandrogen, including those with visceral metastases. Utilization of ADT + docetaxel was lower in patients ≥75 years old while use of ADT + novel hormonal therapy was similar across age groups:
Among patients with more severe disease (ie. with visceral metastasis), the risk of death was similar between 2010-2013 and 2014-2016 groups and was reduced by 26% (vs 2010-2013; HR 0.74, 95% CI 0.63-0.87) in the 2017-2018 group:
For both age groups (<75 and ≥75 years old at treatment initiation), OS improved in 2014-2016 and 2017-2018 after the emergence of docetaxel and novel hormonal therapy as life-prolonging treatments.
Dr. George concluded his presentation with the following take-home messages:
- In this large, nationally representative sample, mCSPC treatment intensification occurred more frequently among patients with bone and/or visceral metastases than those with node-only metastasis
- Adoption of ADT + docetaxel was lower among older patients, though uptake of ADT + novel hormonal therapy was similar regardless of age
- However, the majority of patients with visceral metastases, even in the more recent time, still received ADT-only or ADT + nonsteroidal antiandrogen, despite docetaxel and novel hormonal therapy availability in 2017- 2018
- OS improved over time, which coincided with the introduction of docetaxel and novel hormone agents with mCSPC
Presented by: Daniel J. George, MD, Duke University School of Medicine, Duke Cancer Institute, Durham, NC
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.