Abstract C060: Prostate cancer outcomes in a cohort of unfavorable-intermediate and high-risk patients who underwent external beam radiation therapy at military treatment facilities from 1990 to 2017: Comparing African American and White patients

Abstract Introduction: Previous studies reported that African American prostate cancer (PCa) patients have a higher risk of disease progression and poorer overall survival compared to White PCa patients. In this study, we aim to examine a potential racial difference in PCa outcomes among unfavorable-intermediate and high-risk patients who underwent external beam radiation therapy (EBRT), in a longitudinal cohort of patients with comparable access to cancer care at military treatment facilities. Materials and Methods: Male patients who underwent EBRT for newly diagnosed National Comprehensive Cancer Network-defined unfavorable-intermediate or high-risk PCa, and enrolled in the Center for Prostate Disease Research Multicenter National Database between 2007-2017 were included (self-reported African American, n=249; White, n=633). Multivariable Cox regression analyses were conducted to examine differences in overall survival, biochemical recurrence free survival (BRFS), and distant metastasis-free survival (DMFS) between African American and White prostate cancer patients. Adjusted variables include age at diagnosis, number of comorbidities, smoking status, body mass index (BMI), prostate-specific antigen (PSA), Gleason score, clinical T stage, and receipt of hormone treatment. Results: Compared to White PCa patients, African American patients were likely to be diagnosed at younger age (68 vs White: 71 years), had higher PSA at diagnosis (21 vs. 15 ng/mL), higher BMI, a higher number of comorbidities, and received more aggressive treatment EBRT ≥75 Gy or EBRT with Brachy. Among unfavorable intermediate or high-risk PCa patients who were treated with EBRT, there were no differences between African American and White patients in overall survival (p=0.74), DMFS (p=0.57), and BRFS (p=0.52). Higher PSA at diagnosis was a strong predictor for poorer overall survival (p=0.02), BRFS (p0.001) and DMFS (p=0.004). Conclusions: With comparable access to cancer care, we observed no differences in prostate cancer outcomes between African American and White patients who underwent radiation therapy. Disclaimer: The contents of this publication are the sole responsibility of the author(s) and do not necessarily reflect the views, opinions or policies of USUHS, HJF, the DoD or the Departments of the Army, Navy or Air Force. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government. Citation Format: Jongeun Rhee, Natasza Posielski, Jiji Jiang, Andie Florio, Sally Elsamanoudi, Gregory T. Chesnut. Prostate cancer outcomes in a cohort of unfavorable-intermediate and high-risk patients who underwent external beam radiation therapy at military treatment facilities from 1990 to 2017: Comparing African American and White patients abstract. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr C060.