(UroToday.com) The 2024 GU ASCO annual meeting featured a prostate cancer session and a presentation by Dr. Judd Moul discussing real-world analyses of mortality risk after ADT initiation in Black versus White patients with prostate cancer. There are two studies that found significantly longer overall survival in Black vs. White patients with metastatic castration-resistant prostate cancer: a 2019 meta-analysis of 9 phase III trials regarding docetaxel1 and a 2020 registry study for sipuleucel-T.2 This real-world data study compared all-cause mortality risk for Black vs. White prostate cancer patients. Compared to the prior studies, this study encompasses a broader scope and is not exclusive to men with castration-resistant prostate cancer.
Data were collected from the Decision Resources Group Real World Evidence repository, which links medical and prescription claims, and US Electronic Healthcare Records. The analysis set included prostate cancer patients who received ≥1 ADT injection between 1991-2020. Cox regression was used to compare all-cause mortality rates between White and Black patients. Multivariable regression model accounted for the following variables:
- Baseline metastasis
- BMI
- Oncology vs. urology setting
- Antagonist vs. agonist
- Personal major adverse cardiovascular event (MACE) history
- Tobacco history
- Baseline PSA (>4 vs. ≤4 ng/mL)
- Race (White vs. Black)
- Statin use
- Increasing age per year
- Ethnicity (non-Hispanic vs. Hispanic)
- Increasing ADT exposure per year
- Diabetes
- Hypertension
- Family MACE history
There were 44,439 patients included for the all-patient analyses, and 34,762 patients included in the Black vs White analyses: 5,817 Black men and 28,945 were White men:
Overall, mortality risk was 2.6% and 17% at 1 and 4 years after ADT initiation, respectively:
Mortality risk after ADT initiation was 1.6% and 2.6% at 1 year and 11.7% and 18.1% at 4 years for Black and White patients, respectively:
Both unadjusted (HR 1.66, 95% CI 1.53-1.80) and adjusted (HR 1.24, 95% CI 1.01-1.52) mortality risks were higher for White vs. Black patients:
Additionally, mortality risk was higher for patients with BMI < 18.5 vs >= 18.5 kg/m2 (HR 2.91, 95% CI 2.23-3.80). Dr. Moul provided several discussion points regarding the aforementioned data:
- Potential hypotheses for higher mortality in White vs. Black patients include survival bias to MACE (ie. Black patients may have died from prostate cancer before having MACE), survival bias to be diagnosed with prostate cancer (i.e., Black patients may have higher rate of cardiovascular death and kidney failure prior to prostate cancer diagnosis), and protective effects of higher BMI in Black patients against cancer cachexia
- The large size (~45,000 patients from a database with >300 million patients), long follow-up (10 years for some patients), recent clinical experience (99% from 2010-2020), and diversity of the dataset give weight to the results being an accurate representation of current clinical experience
Dr. Moul concluded his presentation discussing real-world analyses of mortality risk after ADT initiation in Black versus White patients with prostate cancer with the following take-home points:
- All-cause mortality incidence was higher in White vs. Black patients
- BMI and race are largely independent and do not account for the other factor’s increased mortality risk
- Adding to the body of evidence, this study also reveals that Black race is associated with a protective effect on survival for all-cause mortality in men undergoing ADT
- Future studies should confirm these findings that White prostate cancer patients have higher mortality risk and investigate the above hypotheses
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Presented by: Judd W. Moul, MD, Duke University Trent Center for Bioethics Humanities and History of Medicine, Durham, NC
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Associate Professor of Urology, Georgia Cancer Center, Wellstar MCG Health, @zklaassen_md on Twitter during the 2024 American Society of Clinical Oncology Genitourinary (ASCO GU) Cancers Symposium, San Francisco, CA, January 25th – January 27th, 2024
Related content: Analyzing Real-World Impact of Race on ADT Mortality in Prostate Cancer - Judd Moul
References:
- Halabi S, Dutta S, Tangen CM, et al. Overall survival of Black and White Men with Metastatic Castration-Resistant Prostate Cancer Treated with Docetaxel. J Clin Oncol. 2019 Feb 10;37(5):403-410.
- Sartor O, Armstrong AJ, Ahaghotu C, McLeod DG, et al. Survival of African-American and Caucasian men after sipuleucel-T immunotherapy: Outcomes from the PROCEED registry. Prostate Cancer Prostatic Dis. 2020 Sep;23(3):517-526.