Chemotherapy drugs are "cytotoxic" (cell-killing) drugs. They are given orally or by injection. They work systemically by killing cancer cells throughout the body. (Unfortunately, they also kill some normal cells, which accounts for many of their side effects.) Chemotherapy is always used for advanced breast cancer, but may also be used to treat types of early-stage breast cancer.
Newer biologic drugs target specific proteins involved in cancer. Treatment with these drugs is called targeted therapy. Because targeted therapy drugs do not work as systemically as chemotherapy or hormone-blocking drugs, they tend to cause fewer widespread side effects, although they also carry risks of their own
Chemotherapy needs to be tailored to the type of cancer involved. Women require different treatments depending on whether the tumor is node-negative or -positive, hormone receptor-positive or -negative, or HER2-positive or -negative. Different treatment approaches are also used for early-stage cancer and advanced cancer.
Adjuvant chemotherapy is administered following surgery and before radiation therapy. Delaying chemotherapy until more than 12 weeks after surgery may increase the risk for breast cancer recurrence and reduce the odds for survival.
Chemotherapy Drug Classes
Many different types of chemotherapy drugs are used to treat breast cancer. Common types of chemotherapy drug classes include:
Review Date: 11/08/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.