[Aromatase inhibitors in the adjuvant therapy of breast carcinomas]

Hormonal therapies have been used in the adjuvant therapy of breast cancer for decades. Tamoxifen, a selective estrogen receptor modulator, is the current standard therapy. It reduces the risk of recurrence by about one half Only recently, new aromatase inhibitors (anastrozole, letrozole, exemestane) have been competing with tamoxifen; these drugs are superior to tamoxifen in advanced breast cancer. Two recent trials are discussed: Anastrozole reduced the short-term risk of recurrent disease more efficiently than tamoxifen. The use of letrozole after five years of adjuvant tamoxifen treatment further reduced the risk of recurrence. Numerous side-effects, notably endometrial cancer and thromboembolic disease, were less frequent with aromatase inhibitors whereas the risk of osteoporotic fractures increased substantially. The positive preliminary results of these and other trials are discussed: At present, the use of aromatase inhibitors is not yet recommended on a routine basis. Future trial results will allow a more complete assessment of the efficacy and toxicity of aromatase inhibitors.