X-Rays Studied for Breast Cancer Risk
Chest X-Rays May Raise Breast Cancer Risk in Women With Breast Cancer Gene Mutations
June 28, 2006 -- Chest X-rays may raise breast cancerbreast cancer risk in women with the breastcancercancer gene mutations BRCA1 or BRCA2, a new study shows.
Don't rush past that word "may." The researchers aren't totally certain of their findings, so they're not giving any advice just yet.
The data need to be confirmed "before definite clinical recommendations can be made," write Nadine Andrieu, PhD, and colleagues. Andrieu works for France's national institute of health and medical research (Institut National de la Sante et de la Recherche Medicale, or INSERM).
But if the findings are correct, magnetic resonance imaging (MRI) might be a better imaging option than mammography for some women at high genetic risk for breast cancer, states a journal editorial.
Breast Cancer Gene Mutations
Andrieu's study focused on women with the BRCA1 and BRCA2 gene mutations, which greatly raise the risk of breast and ovarian cancers.
The BRCA1 and BRCA2 gene mutations are rare; they're carried by an estimated 250,000 U.S. women, states the Susan G. Komen Breast Cancer Foundation's web site. Inherited gene mutations account for 5% to 10% of breast cancers diagnosed in the U.S., according to the Komen Foundation.
Here's how the Komen Foundation puts the risk in perspective: "A woman's odds of developing breast cancer in her lifetime (assuming she lives until the age of 85) are a bit over 13% if she does not have a BRCA1 or BRCA2 mutation, 60% to 80% if she has a BRCA1 mutation, and 30% to 85% if she has a BRCA2 mutation."
Other gene mutations may also affect breast cancer risk.
Breast Cancer Study
Andrieu's study included 1,601 European and Canadian women with the BRCA1 or BRCA2 gene mutations. The group included 853 women with breast cancer.
When the women were about 47 years old, on average, they completed questionnaires that asked how many chest X-rays -- not counting mammograms -- they had had before and after age 20.
About a quarter of the women reported no chest X-rays, while 970 women noted at least one chest X-ray. Data about chest X-rays was missing for the remaining participants, who made up about 15% of the entire group.