Advances in First-Line Treatment for Patients with HER-2+ Metastatic Breast Cancer

Background. The prognosis for breast cancer patients overexpressing human epidermal growth factor receptor (HER)-2 has changed with anti-HER-2-targeted therapy. Although anti-HER-2 therapy with trastuzumab and chemotherapy is the standard first-line treatment, the best therapeutic regimen has yet to be defined, and new strategies are evolving. Methods. A literature review of well-established and recently published trials, reviews, and ongoing clinical trials addressing first-line treatment for HER-2(+) metastatic breast cancer patients was performed. Results. Taxanes are the agents most commonly used in combination with trastuzumab, but other chemotherapy drugs, such as anthracyclines, vinorelbine, and gemcitabine and triple-combination therapies including platinum compounds, capecitabine, and taxanes have been studied. The combination of aromatase inhibitors with anti-HER-2 therapies is a new therapeutic option for some patients who coexpress HER-2 and hormone receptors, although its activity observed in randomized clinical trials seems to be inferior to that of chemotherapy plus anti-HER-2 therapies. In addition, new anti-HER-2 therapies have shown activity in HER-2(+) tumors, both alone and in combination with trastuzumab. Conclusions. Trastuzumab plus chemotherapy is the current standard of care for the upfront treatment of HER-2(+) breast cancer patients, though other anti-HER2-targeting agents may appear as new standards in the upcoming years. The Oncologist 2012;17:631-644