Breast Cancer Treatment: Radiation therapy

External radiation therapy uses a machine outside the body to send radiation toward the cancer. Usually given each day, Monday through Friday, over a number of weeks, the procedure lasts only minutes. It is painless and is similar to having an X-ray.

As a treatment for breast cancer, external radiation therapy is used most commonly. It is typically given after breast-conserving therapy or mastectomy (once the area has a chance to heal) to kill any cancer cells that may still be in the breast, chest wall or underarm area. If chemotherapy is also being provided, treatment with radiation may not occur until after the chemotherapy is complete.

Internal radiation therapy (sometimes called brachytherapy) uses a radioactive substance sealed in needles, seeds, wires or catheters that are placed directly into or near the cancer.

For patients with breast cancer, the radioactive seeds or pellets are placed into the breast tissue next to the cancer. There are several types of internal radiation therapy. This type of treatment can be used as a way to add an extra boost of radiation to the tumor site. It may be combined with external radiation to breast or used alone. Factors such as the size of the breast tumor and tumor location determine if internal radiation therapy is appropriate.