HER-2 overexpression/amplification and its interaction with taxane-based therapy in breast cancer

Breast cancer (BC) is the most common cancer in women and it is incurable when metastases are diagnosed. Taxanes, namely docetaxel and paclitaxel, are effective chemotherapeutic agents in the metastatic, neoadjuvant and adjuvant settings. HER-2 overexpression/amplification is detected in 25-30% of BCs and confers aggressive tumor behavior as well as resistance to some systemic treatments; nevertheless, its association with response to taxane-based chemotherapy is still unclear, with conflicting results in both in vitro and in vivo preclinical studies. This review will address the impact of HER-2 overexpression/amplification in BC patients treated with taxanes. Prospective, randomized trials incorporating important biological hypotheses are either ongoing or just closed, and their results will hopefully help to shed more light on this issue.