Brain metastases in breast cancer: clinical and pathologic characteristics associated with improvements in survival

Background As breast cancer patients live longer with control of systemic disease, survival after the diagnosis of brain metastases (BM) also appears to be improving. Methods The authors conducted a retrospective review of 112 breast cancer patients diagnosed with BM from 1997 to 2007 and correlated clinical and pathologic characteristics including hormone receptor (HR) and Her2/neu status with outcomes. Findings Median time to BM diagnosis (TTBM) was 38 months (range, 0-204 months). TTBM was shorter for patients with HR- versus HR+ disease (median 28.8 vs. 61.2 months, P < 0.001, Wilcoxon test). No difference in TTBM was observed for patients with HER2- versus HER2+ disease (median 37.4 vs. 34.9 months, P = 0.81). Median survival after the diagnosis of BM was 14.4 months. There was no significant difference in median survival after BM diagnosis for patients with HR+ versus HR- cancers (19.9 vs. 11.0 months, P = 0.18, log rank) or for patients with HER2+ versus HER2- disease (23.1 vs. 13.3 months, P = 0.11, log rank). Survival was significantly longer in patients with stable or responding systemic disease at BM diagnosis compared to patients with progressing systemic disease (31 vs. 6.3 months, P < 0.001). Multivariate analysis revealed that HR positivity, age <50, Karnofsky Performance Score (KPS) 80, and stable or responding systemic disease at BM diagnosis were associated with improved survival. Interpretation Subsets of patients with breast cancer BM are surviving longer. Control of systemic disease was most strongly associated with improved outcomes, and HER2/neu overexpression did not shorten survival after the diagnosis of BM.