Chest Radiation in Childhood a Risk Factor for Breast Cancer in Adult Women

Surviving childhood cancer may only be the beginning for women whose treatment included chest radiotherapy, a new study shows.

According to findings reported online in the Journal of Clinical Oncology by Chaya S. Moskowitz, PhD, of Memorial Sloan-Kettering Cancer Center and colleagues, these women have a breast cancer risk that is 20 times higher than women without such a history in the general population.

It gets worse: Of the women who do go on to develop breast cancer, as many as one fifth of them die of the disease within 10 years of diagnosis, a figure that is double that of women with newly diagnosed breast cancer.

Researchers studied 1,230 female survivors of childhood cancer who had been treated with chest radiotherapy. Among 1230 average women, researchers would expect to find between 9 and 10 cases of breast cancer, but among this cohort they found 203 cases.

"Those treated with whole-lung irradiation have a greater risk of breast cancer than previously recognized, demonstrating the importance of radiation volume," they wrote. "Importantly, mortality associated with breast cancer after childhood cancer is substantial."

They found that the median time from diagnosis of childhood cancer to the onset of breast cancer was 23 years. The median age at breast cancer diagnosis was 39.

Typically, survivors of Hodgkin's lymphoma have had a high risk of breast cancer later in life because of the established use of chest irradiation in treating that disease. In fact, researchers noted that "the cumulative breast cancer risk is remarkably similar between BRCA1 carriers and Hodgkin lymphoma survivors."

They pressed for providing women who received chest irradiation for childhood cancer "a model of care involving risk communication and counseling, breast cancer surveillance, and prevention strategies" similar to that used with women who have a high familial risk of breast cancer.

Source: MedPage Today