Chemotherapy is a systemic therapy used to kill or disable cancer cells that may have spread to the lymph nodes or to other parts of the body. It lowers the risk of breast cancer recurrence.

For people with early breast cancer, chemotherapy is usually given after surgery, but before radiation therapy. When used after surgery, it’s referred to as adjuvant chemotherapy.

Sometimes, chemotherapy is used before surgery. This is referred to as neoadjuvant or preoperative chemotherapy. In women with large tumors who need a mastectomy, neoadjuvant chemotherapy may shrink the tumor enough so a lumpectomy becomes an option.

In women with locally advanced breast cancer, neoadjuvant chemotherapy can reduce the size of the tumor in the breast and/or in the lymph nodes, making it easier to surgically remove the cancer.

In some cases, response to neoadjuvant chemotherapy can help guide treatment after breast cancer surgery.

The treatment schedule for chemotherapy depends on the specific drugs being given. Often, chemotherapy is given in cycles with days or weeks between treatments to give your body a chance to recover between treatments. A full course of chemotherapy for early or locally advanced breast cancer is usually given over 3 to 6 months.