[Aromatase inhibitors in the therapy for breast cancer].

Background: Endocrine therapy plays a key role in the treatment of breast cancer. Because of high efficacy and low toxicity, endocrine therapy is the first-line treatment of advanced pre- as well as post-menopausal breast cancer. In the adjuvant setting, endocrine therapy has a more profound effect on survival compared to chemotherapy in postmenopausal women harboring receptor positive tumors.

New Therapeutic Modalities: The introduction of the novel third-generation aromatase inhibitors is the most important improvement in endocrine therapy since the introduction of tamoxifen 20 years ago. Thus, phase III studies have shown improved efficacy of these compounds compared to conventional therapy at relapse. Based on preliminary results from large phase III studies, aromfase inhibitors are now to be implemented as adjuvant therapy for postmenopausal women.

Future Perspectives: The uncertainties relate to which drug should be used, regimen (monotherapy or sequential treatment with tamoxifen), and potential toxic effects related to long-term oestrogen deprivation.