Young girls who survived Wilms tumor, a rare childhood kidney cancer, were at higher risk for breast cancer later in life because of their exposure to radiation, according to a new study led by Dr. Norman Breslow, professor emeritus of biostatistics at the University of Washington School of Public Health and Member of the Fred Hutchinson Cancer Research Center.
The study, published online in Cancer, found that 15 to 20 percent of Wilms tumor survivors who received radiation to the chest had developed breast cancer by the age of 40. That is nearly 30 times the rate expected among women of a comparable age in the general population. Researchers also found a moderate risk of breast cancer among Wilms tumor patients who received abdominal but no chest radiation.
“Our results suggest that the risk of early breast cancer among Wilms tumor survivors is sufficiently high that early screening might be considered an option for them,” said Dr. Breslow. Current guidelines call for early screening for childhood cancer survivors if they have receive a dose of 20 or more Gray of radiation therapy (Gray is a unit of radiation absorbed by the body). Most Wilms tumor patients typically receive a dose of 12 Gray.
The analysis was based on data from nearly 2,500 females in North America from the National Wilms Tumor Study. The paper’s first author was Dr. Jane M. Lange, who received her PhD in Biostatistics from the UW School of Public Health earlier this year.