Wilms Tumor Survivors at Increased Risk of Breast Cancer

Breast cancer screening guidelines should be reevaluated for women who survived treatment for pulmonary metastases from Wilms tumor, according to a study published early online in the journal CANCER.

Researchers from the University of Washington and the Fred Hutchinson Cancer Research Center in Seattle, Northwestern University in Chicago, Illinois, and St. Jude's Children's Research Hospital in Memphis, Tennessee, investigated whether female survivors of Wilms tumor had an increased risk of breast cancer, following radiotherapy for the disease.

The researchers identified 2,492 girls who had participated in the National Wilms Tumor Studies 1 through 2 (1969 to 1995), and who were followed from the age of 15 until mid-2013. Usual treatment was a relatively low dose of 12-14 Gray of radiation therapy to the entire chest.

The results showed that over 20% of female Wilms tumor survivors who received radiation to the chest, developed breast cancer by age 40 (75% of this group had invasive cancer). However, only 0.3% of female Wilms tumor survivors who did not receive radiation developed breast cancer. There was an intermediate risk (4%) of breast cancer among female Wilms tumor patients who had received abdominal radiation, but no chest radiation. The standard incidence ratios for females receiving chest irradiation, abdominal radiation, and no radiation were 27.6, 6.0, and 2.2 compared to the general population.

"Current guidelines call for early screening for breast cancer among survivors of childhood cancer if they have received 20 or more Gray of radiation therapy to breast tissue. This would exclude a large majority of patients who had received whole chest radiation for Wilms tumor," coauthor Norman Breslow, PhD, University of Washington and the Fred Hutchinson Cancer Research Center, said in a release. "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 also."