Abstract PS4-12-07: Correlations between Race and Area Deprivation Index (ADI) on Treatment and Outcomes in Metastatic TNBC

Abstract Introduction: Previous data has determined that social determinants of health (SDOH) contribute to disparities in breast cancer outcomes. Barriers to treatment and treatment disparities could contribute to this difference, especially as the treatment landscape changes with targeted therapies. This study aims to evaluate the relation between race and area deprivation index (ADI) on treatment disparities and outcomes in patients with metastatic triple negative breast cancer (TNBC). Methods: This is a retrospective review of Caucasian and Black patients treated at the University of Pittsburgh Magee-Womens Hospital diagnosed with metastatic TNBC between 1996-2022. ADI was calculated through the Neighborhood Atlas interactive website from the University of Wisconsin School of Medicine and Public Health, as a percentile ranking from 1 to 100 where higher numbers indicate greater “disadvantage”. Targeted therapies included PARPi, PD-1 and PD-L1 inhibitors, bevacizumab, sacituzumab-govetican. De novo metastatic disease was defined by having initial and metastatic TNBC diagnoses within 2 months. Significance of results was determined using chi-square tests. Results: Of 270 total patients, 237 (87.8%) were Caucasian and 33 (12.2%) Black. ADI quartiles were stratified as Q1 ≤47, Q2 48-69, Q3 70-80, and Q4 80. 59 (21.9%) were diagnosed with primary breast cancer 40 years of age. Median overall survival (OS) of the cohort was 14.1 months after diagnosis of metastatic disease. 46 (17%) patients presented with de novo metastatic disease; 41 (17.3%) Caucasian and 5 (15.2%) Black (p = 0.76). Median time to initiate systemic therapy after diagnosis of metastasis was 35 days in Caucasian patients and 33 days in Black patients. Both Caucasian and Black patients received a median of 3 lines of chemotherapy. 74 (33.9%) of Caucasian patients and 9 (30.0%) of Black patients received targeted therapy (p=0.668). Median time to progression (PFS) was 5.0 months in Caucasian patients and 5.5 months in Black patients. Median OS after diagnosis of metastatic disease was 14.4 months in Caucasians and 13.5 months in Blacks. 110 (46.4%) of Caucasian patients and 18 (54.5%) of Black patients developed CNS metastases (p = 0.381). Stratified by ADI, there was no significant difference in the number of patients presenting with de novo metastatic disease, 12 (17.9%) patients in Q1, 8 (12.7%) in Q2, 9 (13.8%) in Q3, and 12 (19%) in Q4, p = 0.71. Patients in Q1, Q3, and Q4 all had a median of 3 lines of chemotherapy, and Q2 had a median of 2 lines of chemotherapy. No significant difference was seen in the proportion of patients who received targeted therapies between quartiles (Q1 21 (31%), Q2 18 (30%), Q3 18 (29.5%), Q4 26 (42.6%), p = 0.37). Median PFS was similar across Q1-3 at 4.8-5 months, and highest in Q4 at 6.3 months. Median OS after diagnosis of metastatic disease was similar across ADI groups (14.9 months Q1, 14.8 months Q2, 12.8 months Q3, and 14.2 months Q4). Conclusions: There was no significant difference in time to start systemic therapy, number of lines of chemotherapy and proportion receiving targeted therapy in patients with metastatic TNBC, stratified by race and ADI. Similarly, with no difference in treatment parameters, including proportion of patients who received targeted therapy, there was no significant difference seen in progression and OS when stratified by race and ADI. Limitations include that this was a single-center study, and a limited sample size. Further investigation in determining correlations between SDOH, treatment parameters, and outcomes is required in patients with TNBC. Citation Format: A. Chakraborty, B. Jambunathan, A. C. Haley, X. Pei, M. Q. Rosenzweig. Correlations between Race and Area Deprivation Index (ADI) on Treatment and Outcomes in Metastatic TNBC abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS4-12-07.