Trends and Novel Approaches in Neoadjuvant Treatment of Breast Cancer

Breast cancer is the most prevalent malignant disease in women worldwide. Traditionally, surgical tumour resection was the primary step within the treatment algorithm of early stage disease; systemic therapy in order to reduce the rate of systemic recurrences followed. National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-18 found that pre- and postoperative administration of chemotherapy was equally effective. This study therefore established neoadjuvant chemotherapy as a valid treatment option, as the breast conservation rate is increased. Modern neoadjuvant regimens encompassing anthracyclines and taxanes yield pathological complete response (pCR) rates of around 20%, with higher efficacy observed in triple-negative tumours. The antibody trastuzumab is the first targeted agent established in neoadjuvant regimens for the treatment of Her2-positive breast cancer, as it raised pCR rates up to 50%. Novel approaches are aiming to increase the efficacy of neoadjuvant therapy. Inclusion of capecitabine might further increase pCR rates in selected patients, although data are not unanimous throughout the respective clinical trials. In patients harbouring BRCA-1 germline mutations, platinum derivatives are apparently promising. Novel Her2-targeted agents such as lapatinib and pertuzumab are currently under investigation in several clinical trials, while the role of bevacizumab, a monoclonal antibody inhibiting angiogenesis, awaits future clarification.