External radiation therapy is often prescribed 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. Research has shown that radiation to the remaining chest wall tissue reduces the chances of recurrence in that area (called "local recurrence") by 60-75% of whatever the initial risk would have been. These same trials also showed a 25-30% reduction of systemic metastases and even longer survival in those patients who received chest wall radiation.
For women undergoing breast conserving therapy, radiation therapy has been classically given to the entire breast over approximately 6 weeks, followed by a "boost" to the specific site of the primary cancer for approximately 2 more weeks, for a total of 8 weeks of radiation therapy.
Recent studies have suggested that perhaps only the site of the primary cancer needs to be treated, which is called partial breast radiation. Partial breast radiation can be given either from the outside, the way that classic radiation is delivered, or it can be given by inserting radioactive material into the cavity that is left after the primary breast cancer has been removed. The potential advantage of partial breast radiation is that less normal tissue is exposed to radiation. However, this approach is relatively new and it is not clear that it is as safe or as effective as classic radiation. Prospective randomized clinical trials comparing the two methods are now underway at U-M and elsewhere. Browse breast cancer clinical studies on the UMClinicalStudies.org.
Still have questions?
The nurses at Cancer AnswerLine™ have answers. Call 1-800-865-1125 and you'll get a personal response from one of our registered nurses, who have years of experience in caring for people with cancer.