Predictors of surgery refusal and disease-specific survival outcomes in inflammatory breast cancer: A nationally representative cohort study.

e12725 Background: Inflammatory breast cancer (IBC) is a rare but highly aggressive subtype of breast cancer characterized by rapid progression, early metastatic potential, and poor survival compared to non-IBC subtypes. Approximately 10% of breast cancer-related deaths are related to IBC, which accounts for less than 5% of all breast cancer subtypes in the country. Multimodal therapy, including systemic treatment and surgery when indicated, remains central to optimizing disease-specific outcomes; however, not all patients undergo recommended surgical management. In this study, we utilized the Surveillance, Epidemiology, and End Results (SEER) database to evaluate the association between refusal of recommended surgery and disease-specific mortality as well as identify independent predictors of surgical refusal. Methods: The SEER database was queried to identify females diagnosed with histologically-confirmed cases of invasive IBC (ICD-O-3 histology code 8530/3; primary site codes C50.0-50.9) who either received or refused recommended surgery between 2000-2022. Patients with an unknown status of treatment were excluded. Statistical analysis was conducted using SPSS version 29.0.2 and included multivariable binary logistic regression and multivariable cox regressions (significance p < 0.05). Results: A total of 4052 patients were identified, of which the greatest number were non-Hospanic White (66.5%), ages 50-59 (30.3%), resided in urban communities (86.9%), and underwent recommended surgery (98.0%). Multivariable Cox regression adjusting for age, race and ethnicity, annual income, rural-urban living, disease stage at diagnosis, and tumor grade revealed that refusal of recommended surgery was independently associated with a +104% increased disease-specific mortality risk (aHR 2.04; 95% CI 1.27-3.27) compared to those who underwent recommended surgery. Given the observed increase in disease-specific mortality, we next sought to identify independent predictors of recommended surgery refusal. Multivariable binary logistic regression adjusting for the same covariates revealed that Asian and Pacific Islander (API) racial groups were independently associated with +300% greater odds of refusing recommended surgery (aOR 4.00; 95% CI 1.02-15.63). Conclusions: The study highlights significant racial disparities related to surgery refusal, which may help inform patient counseling within affected subgroups and prompt further investigation of barriers contributing to refusal of potentially life-saving treatment. These patterns may reflect underlying sociocultural factors influencing medical decision-making. Our findings are also consistent with prior literature demonstrating higher rates of surgery refusal among API patients across multiple malignancies, including prostate, lung, liver, and gastric cancers.