In interviews with 246 parents who were tested for the BRCA1/2 mutation, 37% supported testing minors, compared with 55% who opposed screening, according to Angela R. Bradbury, MD, of Fox Chase Cancer Center in Philadelphia, and colleagues.
Many professional organizations have recommended against screening youths because of a lack of any medical benefit, according to the study published in the Journal of Clinical Oncology.
"There is no known medical benefit to testing minors in regards to specific medical recommendations," Bradbury told MedPage Today in an e-mail.
Despite these statements, genetic testing of minors for adult hereditary cancer is still being debated. So the researchers decided to assess parent opinion of such testing -- specifically among adults who have had their own testing done.
They conducted interviews with 246 parents at two academic cancer risk assessment programs who'd previously been tested for the BRCA1/2 mutation for breast and ovarian cancer.
The median age of these patients' offspring at the time of the interview was 17 years.
The researchers found that, when asked for a simple yes or no answer, the majority of parents did not support testing of youths in general: 55% were opposed to it and 8% were unsure.
But when given the chance for an open-ended response, that percentage increased to 47%; this group supported testing in some or all circumstances.
The most common reason for opposing screening was parents' perception of the potential for test results to induce fear or anxiety in children. Second to that was the lack of medical indications or proven preventive measures that could be instituted during childhood.
Many parents also "expressed concern that minors were, in general, not sufficiently mature to understand or cope with the information," the researchers wrote.
Most of those who were pro-screening felt the information could result in better health behaviors among children. Those who approved of it in only "some" circumstances did so "in the presence of a medical indication."
Yet the researchers cautioned that it "is of some potential concern that many of these responses suggested a misperception that cancer can occur at exceptionally young ages in some families."
Robert C. Green, MD, MPH, of Boston University, was an investigator on the REVEAL study, which tracked the reactions of patients who were told they have an increased genetic risk for Alzheimer's disease. (That study found that most patients took the news fairly well.)
Green was not involved in the present study, but said he believed the most pressing concern to be the potential psychological impact on children.
"We don't screen in children because it's very hard to predict what the psychological impact would be when people's personalities are still forming," he told MedPage Today.
"We do know that kids are very sensitive to being tracked in school, having other people define their sense of confidence and abilities," he said. "Since we know that there are strong psychological determinants that influence children ... it behooves us to be careful about disclosing information."
When the patients were asked about their own offspring, 44% of those responding to a yes-or-no question said they'd be interested in having them screened. When the question was presented in an open-ended fashion, that number grew to 55%.
Overall, opposition to testing was highest among those with a BRCA1/2 mutation (62%) or with a variant of uncertain significance (74%).
Male sex, less education, and non-white race were all associated with being in favor of screening minors.
The researchers said the proportion of parents who supported testing was somewhat higher than in previous analyses, but that could be due to the increasing comfort with and perceived value of genetic information in this population, or over time.
They also called for further research into the way socioeconomic factors influence perceptions on early testing.
The study was potentially limited by a lack of generalizability, and the subgroup findings need to confirmed in larger trials.
Still, the researchers concluded that "given the lack of evidence supporting either the permission or restriction of BRCA1/2 testing in minors, further evaluation of the risks and benefits of providing genetic risk information and genetic testing to minors for adult-onset disease is needed to inform clinical practice and guidelines."
The researchers reported no conflicts of interest.
Primary source: Journal of Clinical Oncology Source reference: Bradbury AR, et al "Parent opinions regarding the genetic testing of minors for BRCA1/2" J Clin Oncol 2010; DOI: 10.1200/JCO.2009.27.2971.