Paclitaxel: Epirubicin in metastatic breast cancer - a review

Background: Treatment of metastatic breast cancer (MBC) with paclitaxel (T) and doxorubicin has yielded high response rates but the regimen is associated with significant cardiac toxicity. Epirubicin (E) is a less cardiotoxic anthracycline which has also been combined with paclitaxel in the treatment of MBC. Materials and methods: This paper is a review of studies evaluating the pharmacokinetics, toxicity profile, and efficacy of the ET combination in MBC. Results: The ET combination has been studied extensively in Europe. The unique pharmacokinetics of the combination do not lead to the accumulation of cardiotoxic metabolites as in the case of the doxorubicin-paclitaxel combination. In terms of efficacy, the ET combination yields an overall response rate of 50%-70% and complete response rate (CR) 10%-15% in MBC in the same range as the more recent doxorubicin paclitaxel studies. Conclusion: In summary the ET combination is safe and effective in MBC. It is less cardiotoxic than the doxorubicin-paclitaxel combination. Further studies with ET in both the adjuvant setting and in MBC are in progress.