Abstract 2137: Racial disparities in triple-negative breast cancer (TNBC) mortality rates in Hampton Roads Virginia and the effects of SIAH expression on prognosis

Abstract Background: While high-resolution imaging and advancements in therapies have significantly improved breast cancer survival rates, 43, 170 breast cancer patients will die in the United States in 2023 alone. Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype and disproportionately affects BRCA1 mutation carriers and young black women. Black/African American (AA) patients have the highest mortality and the shortest survival of any racial/ethnic group in the US. Persistent cancer racial disparities remain due to a variety of risk factors. The SEER/CDC data show an 8% lower breast cancer incidence rate and a 41% higher mortality rate in Black/AA patients compared to their white counterparts. Methods: Chart review was conducted using Sentara MD Office/EPIC and VOA iKnowMedicine portals to update tumor relapse, metastasis, and survival in 577 TNBC patients. Supported by strong evidence in developmental, evolutionary, and cancer biology, we hypothesize that persistent EGFR/K-RAS/SIAH pathway activation is a major driving force of TNBC malignancy, racial disparity, early relapse, and high mortality. We propose to integrate SIAH expression to augment the existing clinicopathological parameters to improve patient risk stratification, therapy quantification, and relapse/survival prediction at the 1st-line neoadjuvant settings. Results: We report that cancer disparity and high mortality rates are even more pronounced in our racially-diverse communities in Hampton Roads Virginia. We discovered that SIAH is a tumor-specific, therapy-responsive, and prognostic biomarker in TNBC. High SIAH expression in residual tumors reflects tumor-driving EGFR/K-RAS/SIAH pathway activation (ON) that will predict cancer disparity, treatment resistance, early relapse, and poor survival. Low SIAH expression in residual tumors reflect EGFR/K-RAS/SIAH pathway inactivation (OFF) that will predict tumor remission and prolonged survival. Conclusion: We detect a major racial disparity of TNBC patients at Sentara-EVMS-VOA. Our local Black/AA TNBC patients have a 1. 6-fold higher mortality rate than their White counterparts. Encouraged by our preliminary data, we aim to develop a SIAH-centered biomarker panel by measuring the EGFR/K-RAS/SIAH pathway activation (ON) /inactivation (OFF), and use SIAH as a new prognostic biomarker to risk stratify patients, detect cancer racial disparities, forecast tumor relapse, and predict patient survival at 1st-line neoadjuvant settings. By targeting SIAH, individualized treatments can be created to allow for increased survival rates in at risk individuals with more aggressive TNBCs. Citation Format: Claire B. Piatak, Taylor N. Drake, Ashleigh Hannah, Jonathan Baker, Caroline L. Dasom, Emily L. Breeding, Janet S. Winston, Billur Samli, Rick Jansen, Michael Danso, Richard A. Hoefer, Amy H. Tang. Racial disparities in triple-negative breast cancer (TNBC) mortality rates in Hampton Roads Virginia and the effects of SIAH expression on prognosis abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 2137.