Women With Hereditary Breast Cancer Can Safely Have Radiation
Sept. 29, 2000 -- There's some good news for women who have the type of breast cancer associated with the hereditary gene mutations known as BRCA1 and BRCA2. These women may be able to have the breast-conserving procedure lumpectomy, followed by radiation, without worrying that they will suffer more ill effects from the radiation.
Historically, these women have opted for a more aggressive therapy -- mastectomy, or removal of the entire breast. In a lumpectomy, only the tumor is removed, leaving the breast essentially intact, and the patient then undergoes radiation or chemotherapy treatments,
Mutations in the BRCA1 and BRCA2 genes account for about 5-10% of all breast cancers. But doctors have been cautious in how they treat this type of cancer. Because radiation can cause changes in DNA, they were concerned about exposing a mutated breast cancer gene to radiotherapy. Many believed radiation might cause more severe side effects in women with this gene, or even increase the risk that the cancer would return in the treated breast.
But in a study published in The Journal of Clinical Oncology, researchers have found that this does not seem to be the case. The researchers found no significant differences in either radiation side effects or the rate of cancer recurrence in the same breast when they compared women with the BRCA mutations to women who had other forms of breast cancer.
"As near as we know, it is safe," study author David Gaffney, MD, tells WebMD. "Breast-conservation therapy is possible for these patients without additional adverse effects from radiation." Gaffney is an assistant professor of radiation oncology at the University of Utah in Salt Lake City.
The researchers, from several medical centers in the U.S. and Canada, evaluated 71 women with BRCA mutations who had early-stage breast cancer, and compared them with 213 patients who didn't have the gene. Most of the women had undergone lumpectomies, and all had received radiation therapy. Women with the genetic disease experienced no more skin problems or breast pain than the other group. Very few of the patients experienced respiratory problems, but the rates of those who did were similar between the two groups.
Contralateral cancer -- which is when the disease occurs in the other breast -- was seen more frequently in the group with the BRCA breast cancer susceptibility gene. At their five-year follow-up, the researchers found that contralateral cancer had occurred in 15 of the women with BRCA genes, and only four without it.
The study does not address the question of whether contralateral breast cancer rates are higher because of the radiation therapy, says John Daniels, MD, who commented on the study for WebMD. "The authors discuss this and give their opinion, but it is just that," says Daniels, an associate professor of medicine/oncology at the University of Southern California School of Medicine, in Los Angeles.