© 2007 European Society for Medical Oncology
editorial |
Endocrine resistance in breast cancer: what really matters?
1 Department of Breast Medical Oncology, The University of Texas, MD Anderson Cancer Center, USA
* (E-mail: mcristof@mdanderson.org)
| The first 10% of the full text of this article appears below. |
In 1896, George Beatson [1] showed that oophorectomy resulted in tumor remission in a proportion of women with metastatic breast cancer. With over two-thirds of breast cancers demonstrating high expression of estrogen receptor (ER), known to contribute to tumor growth and progression, Beatson's findings revolutionized the management of this disease, paving the way to the discovery of anti-hormonal agents such as tamoxifen, known to selectively modulate the ER. Most recently, aromatase inhibitors that function by preventing extragonadal peripheral estrogen synthesis have also demonstrated clinical activity in various settings. In fact, both classes of agents have been shown in large randomized clinical trials to improve relapse-free survival and to reduce incidence of contralateral breast cancers in women with early-stage breast cancer and overall survival in patients with advanced disease [2–4].
Despite these tremendous advances in the