The US Food and Drug Administration (FDA) recently cleared a new medical device that provides another option for radiation treatment for women who have had a cancerous lump removed from their breast by lumpectomy.

The device, using brachytherapy, is designed to deliver radiation to the surgical site from which the lump has been removed, but not irradiate the rest of the breast.

Brachytherapy is radiation treatment that uses radioactive seeds or pellets that are placed in the area being treated.

The treatment's advantage is that it may be able to substitute for radiation to the whole breast, which is the standard practice today. Besides avoiding radiation to the whole breast, it also takes much less time — just a few days, compared to six weeks for whole breast radiation.

The device is implanted into the breast at the site of the lumpectomy, and the balloon is inflated. A radioactive source is then placed into the catheter. The balloon acts to center the radiation source within the wound. After a series of treatments are completed — typically over several days — the catheter is removed.

The FDA cleared the device based on data from 25 women at eight medical centers who had the device implanted after lumpectomy. The results were that it was comparable in safety and effectiveness to other devices used to deliver brachytherapy to the breast and other body parts.

According to an expert at the American Cancer Society (ACS), brachytherapy has not been proven to be as effective as whole breast radiation in preventing the cancer from coming back in the breast. "It is still considered an experimental procedure", says Herman Kattlove, MD, a medical oncologist and medical editor at the ACS.

"This would be a real benefit for women who have had a lumpectomy for breast cancer because it would save them time and avoid some of the side effects of whole breast irradiation", says Kattlove. "But, we still need to see how it stacks up against whole breast irradiation. Will it be as successful in preventing the cancer from coming back in the breast?"

The new device is called the MammoSite Radiation Therapy System, and is made by Proxima Therapeutics. As a condition for clearance, the FDA is requiring Proxima Therapeutics to include a warning in the product labeling that the safety and effectiveness of MammoSite as a replacement for whole breast irradiation to treat breast cancer has not been established.