Incidence of and survival following brain metastases among women with inflammatory breast cancer

Background: The purpose of this study was to determine the incidence of and survival following brain metastases among women with inflammatory breast cancer (IBC). Patients and methods: Two hundred and three women with newly diagnosed stage III/IV IBC diagnosed from 2003 to 2008, with known Human epidermal growth factor receptor 2 (HER2) and hormone receptor status, were identified. Cumulative incidence of brain metastases was computed. Survival estimates were computed using the Kaplan-Meier product limit method. Multivariable Cox proportional hazards models were fitted to explore the relationship between breast tumor subtype and time to brain metastases. Results: Median follow-up was 20 months. Thirty-two (15.8%) patients developed brain metastases with a cumulative incidence at 1 and 2 years of 2.7% and 18.7%, respectively. Eleven (5.3%) patients developed brain metastases as the first site of recurrence with cumulative incidence at 1 and 2 years of 1.6% and 5.7%, respectively. Compared with women with triple receptor-negative IBC, those with hormone receptor-positive/HER2-negative disease [hazard ratio (HR) = 0.55, 95% confidence interval (CI) 0.19-1.51, P = 0.24] had a decreased risk of developing brain metastases, and those with HER2-positive disease (HR = 1.02, 95% CI 0.43-2.40, P = 0.97) had an increased risk of developing brain metastases, although these associations were not statistically significant. Median survival following a diagnosis of brain metastases was 6 months. Conclusion: Women with newly diagnosed IBC have a high early incidence of brain metastases associated with poor survival and may be an ideal cohort to target for site-specific screening.