Update on aromatase inhibitors in breast cancer

Hormonal treatment is one of the cornerstones of management for breast cancer. For many years, tamoxifen represented the gold standard. The development of aromatase inhibitors has, however, challenged the primary role of tamoxifen. Randomized studies evaluating the role of aromatase inhibitors in both the metastatic and adjuvant settings, in postmenopausal women, have been conducted. This article describes the most recent available data for these trials.

The efficacy of aromatase inhibitors for metastatic disease is well established and has not changed recently. Multiple adjuvant aromatase inhibitor trials have been completed and published or presented. These trials vary in the timing of aromatase inhibitor administration, but all show statistically significant reductions in breast-cancer recurrence. An improvement in overall survival has not been observed to date. Tolerability is improved with aromatase inhibitors, the major concern with the use of aromatase inhibitors being the development of osteoporosis and bone fractures.

Aromatase inhibitors are consistently showing improved efficacy and tolerability to tamoxifen for both early and advanced breast cancer. Optimal therapy for postmenopausal women should include an aromatase inhibitor. The optimal sequence of aromatase inhibitors and tamoxifen for adjuvant therapy is still, however, under investigation.