(P061) Anticoagulation Use and Improved Outcomes in a Predominantly African-American Population With High-Risk Prostate Cancer

Elliot B. Navo, MD, Shan-Chin Chen, Justin Rineer, MD, David Schreiber, MD; Department of Veterans Affairs, NY Harbor Healthcare System, SUNY Downstate Medical Center; MD Anderson Cancer Center Orlando

INTRODUCTION: Several studies have reported improved biochemical and prostate cancer–specific mortality (PSM) outcomes, particularly for men with high-risk (HR) disease, associated with the use of anticoagulation (AC), in addition to radiation therapy. Numerous other studies have suggested that prostate cancer in African-American (AA) men tends to be more aggressive than in Caucasians and/or other races. Therefore, we analyzed our cohort of predominantly AA men with HR disease to determine whether anticoagulation use is associated with any improvements in biochemical or clinical outcomes.

MATERIALS AND METHODS: There were 469 consecutive men treated at the New York Harbor Veterans Hospital with dose-escalated radiation therapy (minimum dose 7,560 cGy) for nonmetastatic prostate cancer between 2003 and 2010. Of these patients, 143 had HR disease and were included in this study. Men were categorized by use of AC at the time of consultation and/or follow-up examinations. Chi-square or Fisher’s exact test was used to compare patient characteristics. Kaplan-Meier curves were generated to compare biochemical-free survival (bFS), distant metastasis–free survival (DMFS), and PSM; outcomes were compared using the log-rank test. Multivariate Cox regression was also performed to identify covariates associated with increased risk for all clinical endpoints.

RESULTS: The median follow-up was 65 months. A total of 55.9% of patients were identified as AA. There were no significant differences in patient characteristics between +AC and −AC. There was significantly improved bFS for AC patients at 5 years (84.6% vs 65.1%; P = .048). The 5-year DMFS was 96.4% for +AC vs 92% for −AC (P = .069). The 5-year PSM was 96.1% for +AC vs 95.9% for −AC (P = .21). On multivariate analysis for biochemical control, only use of AC was associated with improved bFS (hazard ratio [HR] = 0.47; 95% confidence interval [CI], 0.23–0.95; P = .036). AA race was not a significant predictor for biochemical failure (HR = 1.50; 95% CI, 0.50–4.50; P = .47). Similarly, in regard to multivariate analysis for distant metastases, AC was associated with improved DMFS (HR = 0.24; 95% CI, 0.06–0.88; P = .03). However, in regard to PSM, there was no benefit associated with the use of AC (HR = 0.26; 95% CI, 0.05–1.32; P = .10).

CONCLUSIONS: In our population of predominantly minority men with HR disease, the use of anticoagulation is associated with improved bFS and DMFS on multivariate analysis. However, AA race was not associated with any differences in outcome. 

Proceedings of the 97th Annual Meeting of the American Radium Society- americanradiumsociety.org