Despite recommendations and being at an increased risk of breast cancer, most young women who were treated with chest radiation for a childhood cancer do not undergo appropriate mammography screening, according to a study in the January 28 issue of JAMA, the Journal of the American Medical Association.
Women treated with chest radiation for a pediatric malignancy face a significantly increased risk of breast cancer at a young age. "The risk of breast cancer begins to increase as early as 8 years after radiation and the median [midpoint] age of breast cancer diagnosis ranges from 32 to 35 years," the authors write. By age 45 years, it is estimated that from 12 percent to 20 percent of women treated with moderate- to high-dose chest radiation will be diagnosed with breast cancer.
Experts recommend annual screening mammography for women exposed to moderate- to high-dose chest radiation, starting at 25 years of age or 8 years after radiation, whichever occurs last. It is estimated that in the United States there are approximately 20,000 to 25,000 women who are 25 years or older and were treated for a pediatric malignancy with moderate- to high-dose chest radiation. There is limited published information regarding the breast cancer screening practices of women who were treated with chest radiation for a childhood malignancy, according to background information in the article.
Kevin C. Oeffinger, M.D., of Memorial Sloan-Kettering Cancer Center, New York, and colleagues conducted a study that included 625 women, age 25 through 50 years, who had survived pediatric cancer, had been treated with chest radiation and were participating in the Childhood Cancer Survivor Study (CCSS), a North American group of long-term survivors diagnosed from 1970-1986. Participants received a 114-item questionnaire. Comparisons were made with similarly aged pediatric cancer survivors not treated with chest radiation (n = 639) and the siblings of the CCSS group (n = 712). Of 1,976 cancer survivors and siblings who were contacted, 87.9 percent participated.
Among women age 25 through 39 years who had received chest radiation therapy (RT), 36.5 percent reported a screening mammogram within the past 2 years; 47.3 percent had never had a mammogram; and only 23.3 percent had a screening or diagnostic mammogram within the previous year.