Neoadjuvant endocrine therapy for breast cancer: an overview

The clinical benefits of endocrine therapy for patients with hormonosensitive breast cancer remains perfectly established. For instance, tamoxifen, the gold standard of the adjuvant treatment, has largely contributed of the effectiveness of such a therapy. The recent development of new endocrine agents (the third-generation aromatase inhibitors, selective estrogen receptors modulators), provides to physicians the opportunity of a more effective and tolerable therapeutic approach, in the metastatic disease setting or likely in adjuvant setting for breast cancer patients. Preoperative therapy has been widely used for the treatment of initially inoperable locally advanced breast cancers with the main objective of breast-conserving surgery. The benefits of neoadjuvant chemotherapy has widely been demonstrated; however, the success of neoadjuvant endocrine therapy is much recent. The clinical and pharmacological data of the main published studies using neoadjuvant hormonotherapy are presented herein this review. Therefore, clinical and histologic assessments of response brings essential informations about the breast cancer hormonal sensitivity, but may also be predictor of the future (adjuvant or metastatic) treatment responsiveness.