|
Reducing the risk of recurrence in postmenopausal women with early breast cancer: a role for aromatase inhibitors
Fairfax-Northern Virginia Hematology-Oncology, Fairfax, VA
Hormone-dependent early breast cancer is frequently associated with recurrence following surgery, chemotherapy, and adjuvant hormonal treatment. Compared with no therapy or placebo, tamoxifen use as standard adjuvant endocrine therapy in hormone-receptor–positive postmenopausal women with early breast cancer has resulted in improved disease-free survival, a decreased risk of developing contralateral breast cancer, and a survival benefit. However, tamoxifen is associated with an increased incidence of endometrial cancer and thromboembolic events. Third-generation aromatase inhibitors (letrozole, anastrozole, and exemestane) are potent inhibitors of estrogen synthesis with a different side-effect profile from that of tamoxifen. In large, blinded, randomized studies, each inhibitor has proved to be comparable or superior to tamoxifen. Anastrozole lengthened disease-free survival rates and reduced the risk of recurrent breast cancer when used as initial adjuvant therapy, as did letrozole when used as initial and extended adjuvant therapy. Anastrozole and exemestane have reduced the risk of recurrence when either is administered sequentially after tamoxifen in patients who had received 2–3 years of tamoxifen therapy. However, for patients at high risk of early recurrence, it may be better to start therapy with an aromatase inhibitor rather than to wait to switch. Aromatase inhibitors offer improved outcomes over tamoxifen and should be considered as front-line adjuvant hormonal treatment or given sequentially following a course of tamoxifen therapy.
| Commun Oncol 2006;3:275–283 | full text |  178 kb |