Monitoring Pregnancy Is Key After Wilms’ Treatment

Women who received radiation therapy for Wilms’ Tumor are at increased risk of complications during pregnancy and, therefore, should be carefully assessed and monitored by their obstetricians. These conclusions were part of a National Wilms’ Tumor Study Group (NWTSG) report published in the Journal of Clinical Oncology (20:2506-2513, 2002). Daniel M. Green, MD, department of pediatrics, Roswell Park Cancer Institute, was the lead author.

"This is the first study to evaluate the risk of increased complications of pregnancy due to prior Wilms’ tumor treatment," said Dr. Green. "We found that female survivors of Wilms’ tumor who were treated with radiation are at increased risk for early or threatened labor and that their children are more likely to be premature and may be at increased risk of certain congenital defects. These increased complications were not seen in the partners of male survivors of Wilms’ tumor who received the same treatment."

Complications and Congenital Malformations

The study was limited to pregnancies of patients or partners of patients who received either no abdominal irradiation or only flank irradiation as part of their initial course of treatment. The NWTSG reviewed reports of 427 pregnancies with a duration of 20 weeks or more, including 409 liveborn singletons. The most common complications identified during pregnancy included malposition of the fetus and early or threatened labor. Offspring of the irradiated women were more likely to have a low birthweight and be premature (less than 36 weeks’ gestation). An increased percentage had one or more congenital malformations such as cleft lip and palate, undescended testes, or clubfoot.

"We found that the identified complications were more frequent among women who received a higher radiation therapy dose," said Dr. Green. "Additional research is needed to validate these observations and determine if survivors who received lower flank radiation therapy are less likely to have these complications with a pregnancy. Survivors and their physicians must be aware of these issues when guiding a pregnancy to term."