According to study author Maarte Hooning of Eramus Medical Center in Rotterdam, radiation cancer techniques used today will result in a lower dose to the contralateral breast when compared to the techniques examined in the study. However clinicians should be aware of the existing dose-response relationship for risk of contralateral breast cancer.
He adds that especially in young women, radiation exposure to the contralateral breast should be kept as minimal as possible. Although radiation treatment didn’t greatly increase the risk of a new cancer in the other breast, taking the entire 7,000-women group as a whole, with data on younger women scrutinized, alarm bells sounded. The study discovered that cancer risk in the contralateral breast was raised slightly for women under age 45 – but for women under age 35, the enlarged risk rose to 78 percent.
There was also a heightened risk associated with women who received radiation treatment for lumpectomies versus mastectomies. Women under age 45 who received post-lumpectomy radiation were 150 perceived more likely to contract cancer in the opposite breast when compared to women receiving post-mastectomy radiation. Amongst younger women who had an extensive family history of breast cancer and also received post-lumpectomy radiation, the risk for cancer in the other breast increased 350 percent.
However, additional research conducted at The Cancer Institute of New Jersey has found some benefits to a shortened radiation course for patients with the most common form of non-invasive breast cancer. For patients with ductal carcinoma in situ (DCIS), the cancer cells are within the milk ducts of the breast but have not spread to other breast tissue. The study was conducted by Sharad Goyal, M.D., and examined 70 patients between 2002 and 2004 who met specific criteria for the study.
After the study patients underwent lumpectomy, they were offered accelerated partial breast irradiation. This course of treatment is one week in duration and specifically targets the area of the breast where the cancer was removed. Researchers found that, compared to a previous study where radiation therapy was withheld, accelerated partial breast irradiation reduced the recurrence of localized cancer from 6.1 percent to zero percent in low risk patients and from 15.3 percent to 5.3 percent in high risk patients.