Overview of adjuvant systemic therapy in early stage breast cancer.

The benefits of adjuvant systemic therapy in reducing risk of distant relapse from breast cancer have been recognized for several decades. The intent of adjuvant therapy is to eliminate the occult micrometastatic breast cancer burden before it progresses into clinically apparent disease. Successful delivery of effective adjuvant systemic therapy as a complement to surgical management of breast cancer has contributed to the steady declines in breast cancer mortality observed internationally over the past 2 decades. Ongoing clinical and translational research in breast cancer seeks to improve the efficacy of systemic agents for use in the conventional postoperative (adjuvant) setting.