Most young women who received chest radiation for childhood cancer are not being appropriately screened for breast cancer, despite their high risk, according to a recent report.
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 the clinicians are not aware of these patients' high risk, said Dr. Kevin C. Oeffinger of Memorial Sloan-Kettering Cancer Center, New York, and his associates (JAMA 2009;301:404–14).
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 survivors who were diagnosed between 1970 and 1986 as having leukemia, brain tumors, Hodgkin's lymphoma, non-Hodgkin's lymphoma, renal tumors, neuroblastomas, soft-tissue sarcomas, or bone tumors.
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%).
Women in this age group who said their physicians had recommended mammography were three times more likely to undergo screening than were those who said their physicians had not recommended mammography. However, only one-third of these high-risk women said that their physicians had recommended mammography.
The two most commonly reported barriers to screening in this age group were “doctor didn't order it” (31%) and “I'm too young” (30%).
Women aged 40–50 years who had been exposed to radiotherapy fared slightly better, but still only 53% engaged in regular breast cancer screening. In this age group, the most commonly reported barriers to screening were “put it off,” “didn't get around to it,” “too expensive,” or “no insurance.”
In contrast, nearly 90% of the study participants reported having a recent Pap smear, so medical access and knowledge of general women's health issues were not lacking. Instead, “one of the primary barriers is likely a lack of clinician familiarity with childhood cancer survivors and their risk of breast cancer,” Dr. Oeffinger and his colleagues said.
Experts recommend these women start breast surveillance 8 years after radiotherapy or at age 25 years, whichever comes first. ©Brand X Pictures