Background: HER2+ breast cancer is associated with an increased risk of brain metastases (BM). In Asia there is variable utilization of anti-HER2 therapy including trastuzumab (T) and lapatinib (L). This study described anti-HER2 treatment patterns in Asia and evaluated survival after BM in relation to anti-HER2 therapy use. Methods: A retrospective cohort study of 311 Asian patients with HER2+ breast cancer diagnosed with BM between Jan 2006 and Dec 2008 across 14 medical centers in six countries was conducted. Demographics, tumor characteristics, treatment, and dates of all metastases were collected from medical records. Results: Median age was 50 years (range: 23-80). 43% were premenopausal and 43% hormone receptor positive. 76% had multiple brain lesions; 11% had both parenchymal and leptomeningeal involvement. Brain was the first site of metastases in 21%. Prior to BM, 60% (n=186) received anti-HER2 therapy, primarily T in the metastatic setting. These patients had a longer interval between breast cancer diagnosis and BM compared to non-users (median 33 vs. 22 months; p < 0.05). After BM diagnosis, 38% received therapy (N=83 that continued therapy, N=36 new initiators) including 60 T only, 30 L only and 29 that used both T and L administered as sequential (T->L) or add-on (dual blockade) therapy (T->T+L). 93% of anti-HER2 therapy after BM was given along with whole brain radiotherapy (WBRT). Use of anti-HER2 therapy after BM conferred a statistically significantly survival benefit after BM compared to no therapy (median 19 vs. 6 months; HR=0.63, 95%CI: 0.44-0.88 after adjusting for age at BM, other systemic treatment for BM, multiple BM lesions, and BM as first metastatic site). In crude analysis, use of both T and L significantly improved survival compared to T only (median 26 vs. 11 months; crude HR=0.39, 95%CI: 0.20-0.76). Use of both T and L provided a smaller, non-significant survival advantage over L only (median 26 vs. 21 months; crude HR=0.63, 95%CI: 0.29-1.37). Adjusted analyses will be presented. Conclusions: Although only 38% of these Asian patients received anti-HER2 therapy after BM, those receiving therapy had improved survival. Beyond WBRT, the use of both T and L after BM diagnosis may confer a survival benefit over T only or L only regimens.