Emerging research has found that mammograms may actually increase risks for developing breast cancer in some women.
According to The Associated Press (AP), the increased risks were seen in younger women whose genes place them at increased risk for breast cancer—the added radiation from mammograms and other chest radiation testing might be more harmful. The researchers suggest that a magnetic resonance imaging (MRI) scan is likely a safer screening method for women under the age of 30 who are at increased risk for the disease because of gene mutations, the study conducted by leading European cancer agencies, suggests. The research appears in the recent British Medical Journal (BMJ).
Women with BRCA mutations who reside in Britain, the Netherlands, and Spain, are advised to receive MRIs, not mammograms, before age 30. No similar, specific advice has been received in the United States from a leading task force of government advisers; however, the American Cancer Society recommends annual mammograms and MRIs from age 30 on for women with BRCA gene mutations, said the AP.
Although the research did not prove a radiation-breast cancer link, it is one of the largest studies of its kind to review the issue and is not the first time research has suggested such a link. We previously wrote that Dutch research concluded that the low-dose radiation emitted from mammograms and chest X-rays might increase breast cancer risks in susceptible young women. MRIs do not involve radiation.
For this study, Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society—neither the Society nor Lichtenfeld were involved in the research—said, “This will raise questions and caution flags about how we treat women with (gene) mutations.”
Typically, mammograms are used in women over the age of 40, unless the woman is at an increased risk and carries a mutated BRCA1 or BRCA2 gene, explained the AP. These mutations raise risks for developing cancer five-fold and about one in 400 women has one of these abnormalities, which is more typically seen in Eastern European Jewish populations. While breast cancer screening tests have saved lives and proven beneficial for women age 50 and older and who have an average breast cancer risk, said the AP, experts are split about the value of such tests in younger women.
Some research suggests that women with the gene mutations could have increased sensitivity to radiation because the genes involved are also involved in correcting DNA problems, said the AP. If those genes become damaged by radiation, they might be unable to correctly repair DNA, which might raise risks for cancer.
For the current study, the researchers followed about 2,000 women who were over the age of 18; who were diagnosed with one of the gene mutations; and who resided in Britain, France, and the Netherlands, said the AP. The women reported their previous chest X-rays and mammograms, including their age at their first screening and the number of procedures they underwent. According to the AP, about 850 were later diagnosed with breast cancer; about half underwent X-rays and one-third, mammograms, at an average age of 29 years of age.
Although the team did not have details on how may were exposed to chest radiation before age 30, they deduced that for every 100 women who were 30 years of age and with a gene mutation, nine would develop breast cancer by the time they reached 40 years of age, said the AP. The number would increase by five if they had one mammogram before age 30—a figure to be interpreted with caution since most did not undergo a mammogram before age 30.
The team found that women with a history of chest radiation in their 20s had a 43 percent increased relative risk of breast cancer versus women who received no chest radiation, said the AP. Exposure before age 20 increased the risk 62 percent and radiation received after age 30 appeared to have no affect on the risk. “We believe countries who use mammograms in women under 30 should reconsider their guidelines,” said study author Anouk Pijpe of the Netherlands Cancer Institute. “It may be possible to reduce the risk of breast cancer in (high-risk) women by using MRIs, so we believe physicians and patients should consider that,” he added, said the AP.
The previous study on which we wrote found that of the women studied, 8,500 who were exposed to mammogram or chest X-ray radiation prior to turning 20, or those who underwent at least five such exposures, experienced a 2.5 times increased risk of developing breast cancer, versus high-risk women who did not experience the exposure.