Primary endocrine therapy of locally advanced breast cancer patients

Primary endocrine therapy has been traditionally reserved for elderly and unfit locally advanced breast cancer patients (LABC patients). In this group, the primary endocrine therapy could not be adequately compared to primary chemotherapy. Rare studies of primary endocrine therapy, and careful subgroup analyses of their results, showed that primary endocrine therapy could achieve at least the similar magnitude of response rate, compared to primary chemotherapy, in selected patients' population. Thus, the primary treatment with tamoxifen in steroid receptor (SR)-positive LABC patients became the standard arm in current studies of primary endocrine therapy. Several questions, concerning the use of endocrine primary treatment in routine clinical practice, should be answered, including the definition of optimum endocrine agents, biomarkers for prediction of response, and patients' selection criteria