Abstract C037: Inflammatory breast cancer by metastatic status: Racial and ethnic and socioeconomic disparities in receipt of treatment

Abstract Background: Inflammatory breast cancer (IBC) is a relatively rare but aggressive type of breast cancer. Racial and ethnic minority patients are disproportionately affected by IBC and often face barriers to accessing cancer care and services. However, racial and ethnic disparities in receipt of treatment are not well defined among patients with IBC by metastatic status. Methods: We analyzed data from patients with IBC in the 2004-2020 U.S. National Cancer Database. Five treatment modalities were assessed: hormone therapy, chemotherapy, radiotherapy, surgery, and trimodal therapy. Metastatic status was dichotomous as “metastatic/non-metastatic.” Racial and ethnic groups included Asian or Pacific Islander, American Indian, Alaska Native, or Other, Black, Hispanic, and White. Separate logistic regression models were fit, adjusting for sociodemographic and clinicopathological characteristics, stratified by metastatic status. Adjusted odds ratios (aOR) and 95% CIs were calculated. Results: Of 33,376 patients with IBC (mean age 58 years SD=14), most (70.6%) identified as White, followed by 18.1% as Black, 7.0% as Hispanic, 2.5% as Asian or Pacific Islander, 1.8% as American Indian, Alaska Native, or Other; and 32.5% were metastatic. In the non-metastatic cohort, Black (72.7%; aOR 0.79, 95% CI: 0.63-0.98) or Asian or Pacific Islander (74.8%; aOR 0.59, 95% CI: 0.38-0.90) patients had lower odds of receiving hormone therapy than White patients (78.0%). Compared with White patients, Black patients had a lower likelihood of receiving chemotherapy (89.1% vs. 89.5%; aOR 0.67, 95% CI: 0.53-0.86), surgery (78.4% vs. 85.3%; aOR 0.65, 95% CI: 0.55-0.77), or trimodal therapy (81.5% vs. 87.3%; aOR 0.61, 95% CI: 0.49-0.76). American Indian, Alaska Native, or Other (65.0%; aOR 0.64, 95% CI: 0.42-0.97) and Black (63.6%; aOR 0.71, 95% CI: 0.61-0.82) patients had lower odds of receipt of radiotherapy than White patients (70.6%). In the metastatic cohort, Black patients had a lower likelihood of receiving hormone therapy (55.2% vs. 63.5%; aOR 0.61, 95% CI: 0.48-0.78), chemotherapy (78.7% vs. 78.2%; aOR 0.75, 95% CI: 0.60-0.95), surgery (28.2% vs. 35.1%; aOR 0.68, 95% CI: 0.56-0.82), or trimodal therapy (30.4% vs. 40.4%; aOR 0.63, 95% CI: 0.48-0.82) than White patients. There were no statistically significant differences in receipt of treatment between White and other racial and ethnic patients with metastatic IBC. Furthermore, we observed significantly differential rates of treatment receipts by socioeconomic factors including median household income quartile, insurance coverage, and facility type. Conclusions: In this study of a large U.S. national IBC patient cohort, racial and ethnic minority patients were less likely than White patients to have received treatment for IBC, with Black patients being the most affected. Our findings highlight racial and ethnic disparities and socioeconomic inequities in treatment receipts, suggesting the need for oncology programs to improve equitable care access and reduce these disparities in the IBC population. Citation Format: Jincong Q. Freeman, Jared H. Hara, Olasubomi J. Omoleye. Inflammatory breast cancer by metastatic status: Racial and ethnic and socioeconomic disparities in receipt of treatment abstract. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C037.