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Journal of Clinical Oncology, 2006 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 24, No 18S (June 20 Supplement), 2006: 649
© 2006 American Society of Clinical Oncology
Prognostic significance of HER-2/neu over-expression on the incidence of brain metastasis in newly diagnosed breast cancer
B. S. Abdulkarim,
Z. Gabos,
R. Sinha,
J. Hanson,
N. Chauhan,
J. Hugh and
J. Mackey
Cross Cancer Institute, Edmonton, AB, Canada
649
Background: As systemic therapy improves, brain metastases (BM) from breast cancer are becoming increasingly evident. An increased risk of BM in HER-2/neu over-expressing metastatic breast cancer patients has been suggested. However, the relationship between HER-2/neu over-expression and the risk of BM in newly diagnosed breast cancer patients is unknown. Methods: To determine incidence of BM in HER-2/neu over-expressing breast cancer patients, a cohort of patients between 01/1998 and 12/2003 with uniform HER-2/neu testing were identified from a cancer registry. A total of 460 patients with HER-2/neu over-expression and 500 patients with HER-2/neu negative disease were reviewed. Patients were excluded if there was breast cancer diagnosed before 01/1998 or others cancer. A total of 301 HER-2/neu over-expressing and 363 HER-2/neu negative patients were included for this analysis. The association between histological features and the occurrence of BM were evaluated with univariate and multivariate analyses. Results: BM were identified in 8% (24 patients) of HER-2/neu over-expressing breast cancer patients compared to only 1.7% (6 patients) in the HER-2/neu negative patients (hazard ratio 5.15 [2.07912.78], p=0.0001). In patients with recurrent disease, the proportion of BM for HER-2/neu over-expressing patients was 24% compared to 10% in HER-2/neu negative patients. HER-2/neu over-expression, tumor size >2cm, 4 nodes positive and grade 2/3 were predictors of BM in univariate analysis. In multivariate analysis, HER-2/neu over-expression and tumor size>2cm were an independent prognostic factors for the development of BM, while hormone receptors expressions was protective (p=0.02). Conclusions: Our population based study show that newly diagnosed HER-2/neu over-expressing breast cancer patients are at significantly increased risk for BM. As most BM occur in HER-2/neu over-expressing patients with systemic metastatic disease, these findings could prompt consideration of brain prophylaxis strategies and/or serial radiologic screening to detect asymptomatic BM.
No significant financial relationships to disclose.
Abstract presentation from the 2006 ASCO Annual Meeting
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