Impact of systemic therapy on the outcomes of patients with metastatic breast cancer to brain: MD Anderson Cancer Center (MDACC) experience 1999-2012.

1046 Background: Management of metastatic breast cancer to the brain (MBC-B) is mainly surgery and/or radiation. The efficacy of systemic therapy remains controversial. Methods: Out of 1514 consecutive patients (pts) with MBC-B treated at MDACC October 1999-December 2012, 882 had complete data and were included in this retrospective study. We used a Cox multivariate model to identify the effect of any systemic therapy on time-to-progression in the brain (TTP-B) and overall survival (OS). Results: Disease subtypes: ER+/HER2- (26%) ER+/HER2+ (17%); ER-/HER2+ (20%); ER-/HER2- (33%), missing (4%). Number of brain metastasis (BM): 1 (24%), > 1 (67%), concurrent LMD (8%), missing (1%). Local treatment: metastasectomy (S) (5%), stereotactic radio-surgery (SRS) (14%), whole-brain radiation (WBRT) (58%), combination S/SRS with WBRT (12%); no treatment (11%). Subsequent systemic therapy was given to 679 pts (77%). Median OS was 9.7 months (m) (4.0-21.9). Systemic therapy prolonged OS (HR 0.44 CI 0.36-0.52 p < 0.001...