Study Compares Different Types of Radiation for Breast CancerMay 2, 2012
A study comparing a kind of brachytherapy to whole breast irradiation (WBI) found that women treated with brachytherapy were more likely to need more breast surgery later. However, the risk was still low. About 4% of the women in the brachytherapy group needed a mastectomy sometime after radiation was complete versus 2% of the women in the WBI group.
Researchers from the University of Texas MD Anderson Cancer Center examined the medical records from almost 93,000 breast cancer patients who were diagnosed between 2003 and 2007 and had lumpectomy surgery. After the lumpectomy, about 7,000 of the women were treated with brachytherapy and almost 86,000 had WBI. The women treated with brachytherapy were twice as likely (4% vs. 2%) to go on to get a mastectomy of the treated breast – most likely because cancer was found in that breast. There was no difference in survival time between the two groups.
Brachytherapy, also known as internal radiation, is a way to deliver radiation therapy. Instead of aiming radiation beams from outside the body, radioactive seeds or pellets are placed directly into the breast tissue next to the cancer. The kind of brachytherapy in the study, intracavitary brachytherapy, is also the most common way to give brachytherapy to breast cancer patients. It involves putting a source of radiation into the space left from lumpectomy for a short time and then removing it.
The researchers write that brachytherapy has emerged in recent years as an alternative to WBI, which is the standard treatment after lumpectomy. According to the study, as many as 10% of older women are now treated with brachytherapy. Compared with WBI, brachytherapy irradiates less breast tissue and requires a much shorter course of treatment.
This study raises questions about whether irradiating only the area around the cancer will reduce the chances of the cancer coming back as much as giving radiation to the whole breast. More studies comparing the 2 approaches are needed to see if brachytherapy should be used instead of whole breast radiation.
Side effects of WBI can include swelling and heaviness in the breast, sunburn-like skin changes in the treated area, and fatigue. The breast can become smaller and firmer. There is also a risk of painful nerve damage.
Intracavitary brachytherapy can also have side effects, including redness, bruising, breast pain, infection, and a break-down of an area of fat tissue in the breast. As with whole breast radiation, weakness and fracture of the ribs can also occur.
The study was published in the May 2, 2012 issue of the Journal of the American Medical Association.
Association Between Treatment With Brachytherapy vs Whole-Breast Irradiation and Subsequent Mastectomy, Complications, and Survival Among Older Women With Invasive Breast Cancer. Published in the May 2, 2012 issue of the Journal of the American Medical Association (Vol. 307, No. 17). First author: Grace L. Smith, MD, PhD, MPH, University of Texas MD Anderson Cancer Center, Houston, Texas.