Advantages of New Breast Cancer Radiation Treatment

Armen Hareyan's picture

Breast Cancer Radiation Treatment

A new therapy allows women diagnosed with breast cancer to reduce the time needed for radiation treatment.

MammoSite RTS is a form of partial breast irradiation, which delivers radiation from inside the lumpectomy cavity directly to the tissue surrounding the cavity where cancer is most likely to recur.

After the cancerous tumor is removed, two to three weeks later an uninflated MammoSite balloon is placed in the center of the lumpectomy cavity through a small incision in the breast. The balloon is inflated with a saline solution and remains inflated throughout therapy. The catheter is connected to a computer-controlled machine and a tiny radioactive seed travels into the center of the balloon. The seed delivers irradiation to the tumor site and the area immediately surrounding the cavity for a maximum of 10 minutes.

After five days of MammoSite radiation therapy twice a day, the balloon is deflated and removed from the breast.


"The biggest difference between this treatment and the traditional treatment is that patients don't require six weeks of radiation therapy five days a week," said Dr. Kay Blanchard, assistant professor of surgery in the general surgery division of the Michael E. DeBakey Department of Surgery at Baylor College of Medicine.

Currently there are no long-term results showing that patients who receive MammoSite partial breast radiation therapy have as good as or better outcomes than those who receive whole breast radiation therapy. A clinical trial at Baylor College of Medicine is studying whether whole breast radiation therapy is more effective than partial breast radiation therapy in treating women who have undergone surgery for breast cancer.

Patients will be randomly assigned to two groups: group one will receive whole breast radiation therapy once a day five days a week for five to seven weeks and group two will receive partial breast radiation therapy twice a day for five consecutive days. In both groups, patients may receive chemotherapy at least two weeks before or after radiation therapy. Some patients may also receive hormone therapy for at least five years.

Patients will be evaluated at one month, and at every six months for five years, and once a year thereafter.

To be eligible for the study women must be at least 18 years old, have undergone surgery to remove the cancerous tumor, not have Paget's disease of the nipple, had no previous radiation therapy to the breast or chest and no previous biological therapy, chemotherapy or radiation therapy for the cancer.