Most young women who received chest radiation for childhood cancer are not being appropriately screened for breast cancer, despite their high risk.
The primary barrier to screening is not a lack of medical contact; rather, it is that their physicians do not advise them to get mammography, most likely because they are not aware of these patients' high risk, said Dr. Kevin C. Oeffinger of Memorial Sloan-Kettering Cancer Center, New York, and his associates.
Experts recommend that women who were treated with moderate- to high-dose chest radiation for a pediatric malignancy initiate breast cancer surveillance starting at age 25 years, or 8 years after undergoing radiotherapy, whichever comes last. The median age of breast cancer diagnosis in these patients is 32–35 years, and their previous exposure to radiation or anthracycline limits their treatment options.
There are an estimated 20,000–25,000 such women in the United States, and as many as 20% of female cancer survivors worldwide fall into this category.
Dr. Oeffinger and his colleagues studied breast cancer surveillance using the large, geographically diverse population of women participating in the Childhood Cancer Survivor Study. This study follows more than 9,000 cancer survivors who were diagnosed between 1970 and 1986.
A random sample of 551 CCSS participants now aged 25–50 years who received at least 20 Gy of chest radiation therapy as children were surveyed regarding breast cancer surveillance. Two comparison groups—561 CCSS subjects who had not undergone chest radiation and 622 siblings of CCSS subjects who had never had cancer—also were assessed.
Nearly half of the women under age 40 years who had been exposed to pediatric radiotherapy had never had a mammogram, and only 23% had undergone mammography within the preceding year. This “much lower than expected” rate was still somewhat higher than the rates in the CCSS siblings (11%) and the cancer survivors who had not undergone chest radiotherapy (15%). Only one-third of the high-risk women said that their physicians had advised mammography (JAMA 2009;301:404–14).