Abstract
Not all hormone receptor (HR)-positive tumors respond to hormone therapy, although hormone therapy has brought significant benefits to breast cancer patients. In order to improve the efficacy of hormone therapy, a variety of new approaches are currently being tested in such as extended adjuvant therapy, selection of responders using array-based techniques and combination therapy with signal transduction inhibitors. It is therefore necessary to distinguish between highly hormone responsive tumors and relatively less hormone sensitive tumors. Through reviewing recent outcomes of clinical trials, these issues are summarized and discussed in this review.
