Study Links Sex Hormones to Childhood Cancer

Women who take sex hormones before and during pregnancy are threetimes more likely to have children who develop cancer, accordingto researchers at Roswell Park Cancer Institute.

Epidemiologist Arthur Michalek, phd, associate director of theDepartment of Education, and colleagues report that neuroblastoma,the most common type of childhood cancer, is linked to a mother'suse of sex hormones to increase fertility, control vaginal bleeding,or prevent miscarriages.

Neuroblastoma tumors are generally found in adrenal glands. Althoughcancer among young children is rare, neuroblastoma accounts forone-quarter of all childhood cancers and is diagnosed in about500 children annually.

Previously, the low incidence rate of neuroblastomas preventedthe detailed investigation of risk factors associated with thisdisease.

In the Roswell Park study, the first and largest of its kind,Dr. Michalek and associates compared the results of interviewswith 183 women whose children were diagnosed with neuroblastomaand 372 women with healthy offspring. Those mothers who used sexhormones were more likely to have children who were later diagnosedwith the disease.

Male children appeared to be at higher risk for the disease thanfemales, with an average age at diagnosis of 18 months.

Women who took sex hormones to increase fertility proved to beat greatest risk. "The sizable numbers of case and controlmothers interviewed [increased] the statistical power of thisstudy and enabled the detection of subtle risk differences,"explained Michalek.

Although not addressed in the study, the researchers suggest thatother potential risk factors, such as the routine use of oralcontraceptives, be examined in mothers of children diagnosed withneuroblastoma.

A Surprising Development

In a surprising development, vitamins used during pregnancy seemedto offer the unborn child some protection against cancer. Thedata, however, were based on a mother's self-reported use of vitamins,and this aspect of the investigation requires more controlledstudy, Michalek noted.