Lymph node status in inflammatory breast cancer

Positive lymph node status in breast cancer is known to be an adverse prognostic factor, but the effect of lymph node (LN) status in inflammatory breast cancer (IBC) has not been evaluated. This study was designed to investigate the association between lymph node status and overall survival (OS) in individuals with IBC. Using the Surveillance, Epidemiology, and End Results (SEER) 18 registry, we collected data on 761 patients diagnosed with non-metastatic IBC from 2004 to 2008. Survival analysis was performed using the Kaplan-Meier method. Cox proportional hazard regression was performed to evaluate univariate and multivariate associations between estrogen and progesterone receptor (ER/PR) status, treatment, and OS. Positive nodal status was associated with a significant decrease in OS (p < 0.001). Five-year survival for LN-positive and LN-negative patients was 49 and 66 %, respectively. In node-positive patients, ER or PR positivity was associated with improved OS, (p = 0.025, p = 0.007). In node-positive patients, the combination of surgery and radiation therapy improved OS when compared with surgery alone (p = 0.002). Nearly 80 % of the patients in this study had nodal metastasis. Positive nodal status was found to be an adverse prognostic factor. ER/PR positivity and treatment with surgery and radiation in node-positive patients was found to improve outcomes. Further studies are required to characterize the biology of IBC and guide the optimal treatment of this disease.