Racial disparities in clinical outcomes of early-stage triple-negative breast cancer treated with neoadjuvant chemoimmunotherapy: Insights from the NCDB.

602 Background: Triple-negative breast cancer (TNBC) is an aggressive breast cancer (BC) subtype, and Black patients (pts) with TNBC have worse survival outcomes after neoadjuvant chemotherapy, likely due to biological and socioeconomic factors. Neoadjuvant immune checkpoint inhibitors combined with chemotherapy, i.e. neoadjuvant chemoimmunotherapy (NACI) have improved pCR rates and overall survival (OS), but its efficacy by race is unclear. This study evaluates racial disparities in clinical outcomes for pts with early-stage TNBC treated with NACI, aiming to address this critical gap. Methods: We analyzed the National Cancer Database (NCDB) for pts with stage II/III TNBC treated with NACI from 2019 to 2022. Primary outcomes included pCR and OS, which were analyzed with race using univariate and multivariable logistic regression and Cox proportional hazards models, while adjusting for clinicopathologic variables (age, stage, grade, comorbidities (Charlson-Deyo Comorbidity Classification) and socioeconomic factors (residence (rural/urban area), insurance, income). P value ≤0.05 was considered statistically significant. Results: A total of 5,137 pts were included. Median age was 51 years (range:39-63); 69.9% were White, 20.5% Black, 9.6% Other, 49.3% had stage II and 50.7% had stage III TNBC. Median follow up was 26.6 months (3.3-61.9), pCR was achieved in 76.5% pts, (White: 77%, Black: 74%, Other: 76%; p = 0.113). Pts achieving pCR had significantly higher 3-year OS (92% vs 72%, p<0.001) and 5-year OS (84% vs 56%, p<0.001) compared to those without pCR. Racial disparities in survival were observed, with 3-year OS of 88%, 84%, and 85% (p <0.05) and 5-year OS of 83%, 77%, and 85% for White, Black, and Others, respectively (p<0.05). After adjusting for covariates, Black pts had a trend toward lower likelihood of pCR compared to White pts although not statistically significant (odds ratio (OR) 0.76 [95% CI: 0.54–1.07]. The factors independently associated with worse OS were residence in rural areas (HR 1.79 [95% CI: 1.00–3.19], p = 0.05), tumors ≥10 cm (HR 1.92 [95% CI: 1.21–3.06], p = 0.006), stage III disease (HR 1.91[95% CI: 1.47–2.49], p < 0.001) and Black vs. White group (HR 1.42 [95% CI: 1.10–1.84], p = 0.007). Conclusions: Black pts with TNBC receiving NACI have worse OS than White pts, possibly due in part to social, structural, or biological determinants of health. Further research is needed to investigate personalized treatment strategies that address the unique challenges Black pts face in achieving long-term survival and improving overall prognosis. Survival rates and hazard ratios by race. Race 3-year survival rate (%) 5-year survival rate (%) Hazard ratio White 88% 83% 1.00 Black 84% 77% 1.42 [95% CI 1.10–1.84] Other race 85% 85% 1.19 [95% CI 0.82–1.74]