Current and future choices in endocrine therapy

Excerpt

A typical article on choices in endocrine therapy for breast cancer generally focuses on a discussion of the use of an adjuvant aromatase inhibitor versus tamoxifen, a comparison between aromatase inhibitors, the value of ovarian suppression, the use of the steroidal oestrogen fulvestrant, or possible roles for oestrogens and progestins as third-line treatment in the management of advanced disease [1]. To this menu one can now add the use of raloxifene as opposed to tamoxifen as a chemoprevention agent in women at high risk for the disease [2]. All of these options have been examined in randomized clinical trials, but although positive results have been observed, no recent studies have demonstrated an impact on the disease that is close to that seen when tamoxifen was compared with observation in the worldwide overview of randomized tamoxifen trials in breast cancer [3]. One can therefore reasonably conclude that a major phase of drug development in breast cancer endocrine therapy is drawing to a close. Although there may be advances in oestrogen receptor (ER) targeting at the margins, no major breakthrough is likely with the endocrine studies that remain outstanding. The debate is therefore beginning to refocus anew on how we might influence the near constant relapse rate that continues more than a decade after a diagnosis of ER-positive disease, despite the application of our best ER targeting strategies. …