Overall survival is improving among men with de novo metastatic prostate cancer, according to real-world data presented at the American Society of Clinical Oncology’s 2023 Genitourinary Cancers Symposium in San Francisco, California.
Investigators analyzed data from 51,899 men in the Surveillance, Epidemiology and End Results (SEER) database and 14,537 men in the Veterans Health Administration (VHA) system. Median overall survival times in the SEER cohort increased from 24 months during 2000-2004 to 31 months during 2015-2019, Martin W. Schoen, MD, MPH, of Saint Louis Veterans Affairs Medical Center and Saint Louis University in Missouri, reported. In the VHA cohort between those time points, median survival times rose from 25.5 to 30.9 months.
The improvement in overall survival was more modest than observed in clinical trials of prostate cancer medications where patients typically are younger, with fewer comorbid diseases, the authors noted.
In the VHA cohort, Black patients had longer median overall survival in 2015-2019 compared with White patients (31.5 vs 30.6 months), although this difference was of marginal significance. In the SEER population, Black patients had worse survival compared with White patients.
Notably, Black men in the VHA system had significantly better survival compared with those in the SEER registry. “This difference may represent the more equal access to care that the VHA provides, especially for younger Black veterans who may not have access to other insurance, such as Medicare,” Dr Schoen explained.
Improvement in overall survival was more pronounced among patients younger than 70 years. The relatively worse survival among patients aged 70 years or older is likely related to competing risks of death and reduced likelihood of receiving doublet therapy, according to Dr Schoen and colleagues.
In a separate study of 5006 US veterans with de novo metastatic hormone-sensitive prostate cancer (mHSPC), Dr Schoen and colleagues documented an increase in the use of doublet therapy with the VHA system from 2012 to 2021. Doublet therapy is androgen deprivation therapy (ADT) plus either docetaxel or an androgen signaling inhibitor (ASI). ASIs include abiraterone, enzalutamide, apalutamide, and darolutamide. Since 2020, doublet therapy has been used in more than 50% of cases, the investigators reported.
They also concluded that doublet therapy for mHSPC is associated with longer survival.
In an analysis of 2042 patients receiving care during 2018-2021, they found that median overall survival was 29.3 months with ADT alone, 35.3 months with ADT/docetaxel, and 41.2 months for ADT/ASI. Compared with ADT alone, ADT/docetaxel and ADT/ASI were significantly associated with a 28% and 33% lower risk for death.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Schoen MW, Etzioni R, Knoche EM, et al. Treatment and survival of de novo metastatic prostate cancer in US veterans. Presented at: ASCO GU 2023, San Francisco, California, February 16-18. Abstract 87.
Schoen MW, Owens L, Luo S, et. al. Survival trends in de novo metastatic prostate cancer: SEER and Veterans Affairs comparison. Presented at: ASCO GU 2023, San Francisco, California, February 16-18. Abstract 28