The association between local therapies and survival among patients with metastatic inflammatory breast cancer.

Inflammatory breast cancer (IBC) is an aggressive subtype with early metastatic spread. This study evaluated whether adding adjuvant radiation therapy (RT) to surgery and chemotherapy improves survival in metastatic IBC using the National Cancer Database (2010-2021). A total of 3219 patients were categorized into four groups: chemotherapy alone; chemotherapy plus surgery; chemotherapy plus RT; and trimodality therapy (chemotherapy and surgery followed by RT). Median follow-up was 23.6 months. Two-year overall survival was 51.8% (chemotherapy alone), 57.8% (chemotherapy + surgery), 36.5% (chemotherapy + RT), and 73% (trimodality therapy). Compared with chemotherapy + surgery, chemotherapy alone and chemotherapy + RT were associated with higher mortality, while adding adjuvant RT after chemotherapy + surgery (trimodality therapy) was not associated with improved survival. In subgroup analysis, adding PMRT to surgery and chemotherapy in those with positive surgical margins was associated with improved survival compared with surgery and chemotherapy alone, adjusting for age (aHR 0.57; 95% CI: 0.34-0.97). Further research is needed to understand the role of local therapy in metastatic IBC.