The Impact of Locoregional Therapy in Nonmetastatic Inflammatory Breast Cancer: A Population-Based Study

Abstract

Background.Inflammatory breast cancer (IBC) is a rare but most aggressive breast cancer subtype. The impact of locoregional therapy on survival in IBC is controversial.Methods.Patients with nonmetastatic IBC between 1988 and 2013 were identified in the Surveillance, Epidemiology, and End Results (SEER) registry.Results.We identified 7,304 female patients with nonmetastatic inflammatory breast cancer (IBC) who underwent primary tumor surgery. Most patients underwent total mastectomy with only 409 (5.6%) undergoing a partial mastectomy. In addition, 4,559 (62.4%) were also treated with radiation therapy. The patients who underwent mastectomy had better survival compared to partial mastectomy (49% versus 43%,p= 0.003). The addition of radiation therapy was also associated with improved 5-year survival (55% versus 40%,p< 0.001). Multivariate analysis showed that black race HR (1.22, 95% CI 1.18–1.35), ER negative status (HR 1.22, 95% CI 1.16–1.28), and higher grade (HR 1.14, 95% CI 1.07–1.20) were associated with poor outcome. Cox proportional hazards model showed that total mastectomy (HR 0.75, 95% CI 0.65–0.85) and radiation (HR 0.64, 95% CI 0.61–0.69) were associated with improved survival.Conclusions. Optimal locoregional therapy for women with nonmetastatic IBC continues to be mastectomy and radiation therapy. These data reinforce the prevailing treatment algorithm for nonmetastatic IBC.