Weekly taxanes in metastatic breast cancer (review)

Metastatic breast cancer is still considered an incurable and difficult to treat disease, even if several classes of antineoplastic agents have shown various levels of activity in these patients. Taxanes are the most effective drugs in breast cancer, together with the anthracyclines, but they have several important side-effects with standard administration schedules. The weekly administration of both paclitaxel and docetaxel, respectively at 80-100 mg/m2/week and 35-40 mg/m2/week, is feasible and it has an efficacy level at least comparable with the standard 21-day administration. These schedules can also be administered at an increased dose-intensity with a better toxicity profile. Even if most of the data available today come from small phase I and/or II trials, the weekly schedules of taxanes administration are an attractive therapeutic chance, especially (but not only) in the elderly patients. Moreover the minimal side-effects make this approach very interesting for combination therapy with other drugs as well as with new biological agents such as anti-HER-2 and anti-EGF molecules. Ongoing phase III trials will clarify the efficacy of the weekly administration schedules and will define their role in the treatment of the metastatic breast cancer.