Recent Advances in the Neoadjuvant Treatment of Breast Cancer

In the last few decades, neoadjuvant therapy for breast cancer has gained considerable therapeutic importance. Despite extensive clinical investigations, it has not yet been clarified whether neoadjuvant therapy would result in improved survival in comparison with the standard adjuvant setting in any subgroups of patients with breast cancer. Chemotherapy is especially effective in the treatment of endocrine insensitive tumors, and such therapeutic benefit can be assumed for patients with triple-negative, or hormone receptor-negative and human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, dose escalation, modification of the therapeutic regimens according to early tumor response, as well as the optimal sequence of administration are still matters of debate. There is a current debate between clinical experts regarding the concomitant and sequential administration of carboplatin and capecitabine, respectively, as part of the standard neoadjuvant treatment, as well as the use of bevacizumab, as part of the preoperative treatment. In case of HER2 positive tumors, an anti-HER2 agent can be administered as part of the preoperative treatment, and according to preliminary clinical data, dual HER2 blockade can also be reasonable. Further, chemotherapy-free regimens can be justified in highly endocrine sensitive tumors, while immune modulating agents may also gain particular importance in the case of certain sub-types of breast cancer. Several small-molecule targeted therapies are under clinical investigation and are expected to provide new neoadjuvant treatment options. However, novel, more predictive biomarkers are required for further evaluation of the neoadjuvant therapies, as well as the effect of novel targeted agents intended to be incorporated into neoadjuvant therapy.