Advances in the use of taxanes in the adjuvant therapy of breast cancer.

Among the novel chemotherapeutic drugs introduced in the 1990s, the taxanes have emerged as the most powerful compounds in breast cancer. Paclitaxel and docetaxel have been evaluated in the metastatic setting before proceeding with adjuvant trials. The adjuvant strategies of development of both taxanes have been different, mostly as a result of pharmacokinetic differences and dose-schedule issues. As a consequence, paclitaxel was studied nearly exclusively in sequential programs such as AC (doxorubicin/cyclophosphamide) followed by paclitaxel or doxorubicin, followed by paclitaxel, followed by cyclophosphamide. In contrast, docetaxel has been investigated in sequence (AC followed by docetaxel) and in combination chemotherapy (doxorubicin/docetaxel and docetaxel/doxorubicin/cyclophosphamide). Available results of large-scale phase III trials confirm that the taxanes have the potential to change the natural history of early-stage breast cancer. It is becoming clear that sequential chemotherapy and polychemotherapy approaches with taxanes are to be considered in the treatment of patients with node-positive breast cancer. Further results are eagerly awaited to fully understand the role of taxanes and to optimize their impact on early-stage breast cancer. It is our opinion that the real pending issue is no longer whether taxanes will make a difference in the adjuvant setting (the answer is most likely yes), but the definition of their optimal strategic use for maximum patient benefit.