What is chemotherapy?

In cancer treatment, chemotherapy refers to the use of drugs whose main effect is either to kill or to slow the growth of rapidly multiplying cancer cells.

Chemotherapy often includes using a combination of drugs, since this approach is more effective than using a single drug alone. There are many drug combinations used to treat breast cancer. Ask your doctor for specific information and side effects you can expect from your chemotherapy medications.

When is chemotherapy given for breast cancer?

Chemotherapy is sometimes given before surgery (called neoadjuvant treatment) in order to shrink the tumor so it can be removed more easily or so that a lumpectomy can be performed instead of a mastectomy. When breast cancer is localized only to the breast or lymph nodes, chemotherapy may be given after a lumpectomy or mastectomy. This is known as adjuvant treatment and may help reduce the chance of breast cancer recurrence.

Chemotherapy may also be given as the main treatment for women whose cancer has spread to other parts of the body outside of the breast and lymph nodes. This spread is known as metastatic breast cancer and occurs in a small number of women at the time of diagnosis or when the cancer recurs some time after initial treatment for localized breast cancer.