Study backs radiation for ductal breast cancer
Women who undergo breast-conserving surgery to treat the most common type of non-invasive breast cancer could cut the risk of recurrence by adding radiation and drug therapy to their treatment, according to a study conducted by the National Surgical Adjuvant Breast and Bowel Project based at Allegheny General Hospital in Pittsburgh.
The study should reassure women with ductal carcinoma in situ that, after a lumpectomy, additional countermeasures such as radiation are not necessarily an indication of overtreatment, said Dr. Thomas Julian, principal investigator of the study, published today in the Journal of the National Cancer Institute. In DCIS, which accounts for 25 percent of breast cancer diagnoses, cancer cells are lodged in the breast ducts without invading other breast tissues.
"If you have the radiation, it is safe and it can keep the cancer from coming back," said Julian, associate director of the Breast Care Center at AGH in the North Side. Dr. Norman Wolmark, chairman of human oncology, was the senior author. "It's not 100 percent, but it reduces the chances, and therefore you have a better long-term survival."
The incidence of DCIS has increased in the past several years as more women undergo mammogram screenings, according to the National Institutes of Health. The national surgical project at AGH is conducting three trials to examine better treatments for DCIS.
"It's hard to figure out which DCIS will stay dormant, and which will go on to invasive breast cancer," Julian said. "People are struggling to figure out how to better treat women to prevent them from having a bad outcome."
The study, however, justifies treatments involving radiation, the drug tamoxifen, or a combination of the two, Julian said. Radiation after lumpectomy reduced the incidence of a dangerous cancer recurrence by 52 percent, compared to women who had only a lumpectomy. Women with estrogen receptor positive DCIS who added tamoxifen to their treatment cut their risk by 32 percent, compared to those who got lumpectomy and radiation only.