Liposomal anthracyclines: adjuvant and neoadjuvant therapy for breast cancer

Conventional anthracyclines, particularly doxorubicin, have played an important role in the treatment of patients with breast cancer for many decades. Conventional doxorubicin has shown excellent antitumor activity in the metastatic, neoadjuvant, and adjuvant settings. However, its clinical utility is limited due to acute and chronic toxicities, particularly cardiotoxicity, myelosuppression, nausea and vomiting, and alopecia. Liposomal doxorubicin formulations (liposomal doxorubicin [D-99] and pegylated liposomal doxorubicin) currently under investigation for the treatment of breast cancer have demonstrated similar efficacies and favorable toxicity profiles compared with conventional doxorubicin in patients with metastatic breast cancer. These agents have also shown efficacy and tolerability in several small studies as neoadjuvant therapy in patients with locally advanced breast cancer. While there are currently no studies with liposomal doxorubicin or pegylated liposomal doxorubicin as adjuvant therapy, their demonstrated activities and tolerabilities in the metastatic and neoadjuvant settings provide the rationale for the future study of these agents in adjuvant therapy for patients with early-stage breast cancer.