More than 8 percent of children with cancer have gene mutations that increase their risk of cancer, a new study says.
The findings suggest that genetic screening might be important in all childhood cancer patients, not just those with a family history of cancer, according to the researchers with the St. Jude Children's Research Hospital-Washington University Pediatric Cancer Genome Project.
Doing so would improve the chances of detecting cancers at their earliest and most treatable stages, the researchers said.
The researchers analyzed tumor and normal tissues from 1,120 childhood cancer patients and found that 8.5 percent of the children had genetic mutations in their normal tissue that increase the risk of cancer. More than half of the children with these mutations came from families with no history of cancer.
Previously, it was thought that such mutations were rare and occurred only among children in families with a strong history of cancer, according to the study, published in the Nov. 19 issue of the New England Journal of Medicine.
"This paper marks an important turning point in our understanding of pediatric cancer risk and will likely change how patients are evaluated," corresponding author Dr. James Downing, St. Jude president and chief executive officer, said in a news release from the Memphis hospital.
"For many pediatric cancer patients, comprehensive next-generation DNA sequencing of both their tumor and normal tissue may provide valuable information that will not only influence their clinical management but also lead to genetic counseling and testing of their parents and siblings who may be at risk and would benefit from ongoing surveillance," he explained.
"The frequency of 8.5 percent represents our current estimate of the number of pediatric patients with a hereditary cancer predisposition. This number will likely increase as we learn more about mutations in this class of genes in young cancer patients," Downing added.
