Treatment of HER2-positive breast cancer

Breast Cancer Program, The Johns Hopkins Kimmel Comprehensive Cancer Center, Baltimore, MD 21231, USA.
Current Treatment Options in Oncology (Impact Factor: 3.24). 03/2012; 13(2):230-9. DOI: 10.1007/s11864-012-0186-4
Source: PubMed


OPINION STATEMENT: About 15-20% of patients with early stage breast cancer present with tumors that have overexpression or amplification of the human epidermal growth factor receptor 2 (HER2) gene. Before 2005, these individuals had an increased risk of recurrence and death, but since then their outcomes have substantially improved with the adoption in most countries of adjuvant trastuzumab as a standard component of therapy for HER2-positive early-stage breast cancer. Consequently, access to high-quality and accurate HER2 testing methods is critical to accurately determine HER2 status, guide treatment decisions, and ultimately improve clinical outcomes. In 2012, the humanized monoclonal anti-HER antibody trastuzumab was the only approved HER2-targeted therapy in the adjuvant setting. Data from the first generation of trials combining it with various chemotherapy regimens showed significant improvements in disease-free and overall survival (DFS/OS). Based on results from five randomized clinical trials, a trastuzumab-containing regimen for up to 1 year is now considered standard for all patients with HER2-positive tumors larger than 1 cm in size who would have fulfilled eligibility to those studies, and this recommendation is sometimes extended to patients with stage I tumors greater than 0.5 cm (T1b). Second generation adjuvant studies with other HER2-targeted agents like lapatinib and pertuzumab are ongoing, and newer drugs like T-DM1 and neratinib are being actively tested in the metastatic setting.

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    • "Lapatinib is the very first orally available epidermal growth factor receptor/human epidermal growth factor receptor 2 (EGFR/HER2) dual kinase inhibitor approved by the FDA. It is now used as a first-line treatment for HER2-positive breast cancers or metastatic breast cancer patients in combination with capecitabine or letrozole (Gomez et al., 2008; Jelovac & Wolff, 2012). Although lapatinib has demonstrated success in the pharmacotherapy of breast cancer, several issues remain in its clinical use. "
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