Adjuvant and Neoadjuvant Therapy with Lapatinib in ErbB2-Overexpressing Breast Cancer

Since 2001, when Sorlie et al. [1] introduced a molecular classification of breast cancer into at least 4 subgroups, the very heterogenous prognosis of the different subtypes of this disease has been recognized. For clinical use, a more simple subclassification based on hormone receptor status and ErbB2 (HER2) status has been adopted, segregating hormone receptor-positive breast cancer with a relatively benign prognosis, and ErbB2-overexpressing breast tumor and triple-negative tumors with an unfavorable clinical outcome. Women with ErbB2-overexpressing tumors comprise up to 30% of all breast cancer patients and are characterized by a short relapse-free and overall survival [2]. The emergence of ErbB2 as a potential target for therapy and the combination of the anti-ErbB2 antibody trastuzumab with conventional cytotoxic regimens has led to a new era of breast cancer treatment [3].