HER2 POSITIVITY IS ONE OF THE GREATEST RISK FACTORS FOR BRAIN METASTASES IN PATIENTS WITH BREAST CANCER1-6
![Image of brain scans showing development of brain metastases](../../../images/Brain.gif)
![Image of brain scans showing development of brain metastases](../../../images/brain-role.png)
ALMOST
1 in 2 patients
with HER2+ metastatic breast cancer will develop brain metastases over the course of their disease4,6
- Retrospective data show that patients with tumors overexpressing HER2 develop brain metastases at a higher rate than most patients with HER2-negative tumors, including those with the TN subtype1,7
- Brain metastases in patients with HER2+ MBC, as identified by IHC or ISH, can occur even in patients who are otherwise responding to treatment or who have stable disease at other sites8,9
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Images are for illustrative purposes only and are not to scale.
BBB = blood-brain barrier; Da = dalton; HER = human epidermal growth factor receptor; IHC = immunohistochemistry; ISH = in situ hybridization; MBC = metastatic breast cancer; TN = triple-negative.
References: 1. Aversa C, Rossi V, Geuna E, et al. Metastatic breast cancer subtypes and central nervous system metastases. Breast. 2014;23(5):623-628. 2. Bailleux C, Eberst L, Bachelot T. Treatment strategies for breast cancer brain metastases. Br J Cancer. 2021;124(1):142-155. 3. Koniali L, Hadjisavvas A, Constantinidou A, et al. Risk factors for breast cancer brain metastases: a systematic review. Oncotarget. 2020;11(6):650-669. 4. Olson EM, Najita JS, Sohl J, et al. Clinical outcomes and treatment practice patterns of patients with HER2-positive metastatic breast cancer in the post-trastuzumab era. Breast. 2013;22(4):525-531. 5. Bendell JC, Domchek SM, Burstein HJ, et al. Central nervous system metastases in women who receive trastuzumab-based therapy for metastatic breast carcinoma. Cancer. 2003;97(12):2972-2977. 6. Altaha R, Crowell E, Hobbs G, Higa G, Abraham J. Increased risk of brain metastases in patients with HER-2/neu-positive breast carcinoma. Cancer. 2005;103(3):442-443. 7. Wu Q, Li J, Zhu S, et al. Breast cancer subtypes predict the preferential site of distant metastases: a SEER based study. Oncotarget. 2017;8(17):27990-27996. 8. Palmieri D, Bronder JL, Herring JM, et al. Her-2 overexpression increases the metastatic outgrowth of breast cancer cells in the brain. Cancer Res. 2007;67(9):4190-4198. 9. Burstein HJ, Lieberman G, Slamon DJ, Winer EP, Klein P. Isolated central nervous system metastases in patients with HER2-overexpressing advanced breast cancer treated with first-line trastuzumab-based therapy. Ann Oncol. 2005;16(11):1772-1777. 10. Yonemori K, Tsuta K, Ono M, et al. Disruption of the blood brain barrier by brain metastases of triple-negative and basal-type breast cancer but not HER2/neu-positive breast cancer. Cancer. 2010;116(2):302-308. 11. Brosnan EM, Anders CK. Understanding patterns of brain metastasis in breast cancer and designing rational therapeutic strategies. Ann Transl Med. 2018;6(9):163. 12. Witzel I, Oliveira-Ferrer L, Pantel K, Müller V, Wikman H. Breast cancer brain metastases: biology and new clinical perspectives. Breast Cancer Res. 2016;18(8):1-9. 13. Morad G, Carman CV, Hagedorn EJ, et al. Tumor-derived extracellular vesicles breach the intact blood-brain barrier via transcytosis. ACS Nano. 2019;13(12):13853-13865. 14. Pardridge WM. Drug delivery to the brain. J Cereb Blood Flow Metab. 1997;17(7):713-731.