Biological therapy of breast cancer: recent clinical applications.

Advances have been made in breast cancer therapy, in both the adjuvant and metastatic settings. For example, in the adjuvant setting, genomic studies of breast cancer tissues have identified women with estrogen receptor-positive tumors who might not require chemotherapy, leading to the development of a diagnostic tool. There have also been significant developments with anticancer agents that target tumor cell surface receptors, such as HER2/neu, and those involved in angiogenesis and kinase-dependent pathways. New areas of research focus on the concept of breast cancer stem cells as well as the prognostic importance of bone marrow micrometastases in early-stage breast cancer. This review summarizes these advances in breast cancer clinical research.