AT THE AHA SCIENTIFIC SESSIONS

NEW ORLEANS (FRONTLINE MEDICAL NEWS) – Children with congenital heart defects have a five- to sixfold increased risk of developing pediatric cancer, Matthew Oster, MD, reported at the American Heart Association scientific sessions.

“The absolute risk is small, but it’s still a five- to sixfold risk compared to the general pediatric population, and it does warrant monitoring and a high index of suspicion in our children with congenital heart defects,” said Dr. Oster of Children’s Healthcare of Atlanta.

The increased cancer risk in adults with congenital heart defects has recently been the focus of research attention. However, little is known about the risk of cancer during the childhood of patients with congenital heart defects.

This was the impetus for Dr. Oster’s nationwide retrospective study of 6.1 million children and adolescents continuously enrolled in private, employer-sponsored health insurance plans during 2009-2015. The data came from the Truven Health MarketScan administrative database.

Children with Down syndrome were excluded from the study because their condition is known to be associated with increased rates of both congenital heart defects and pediatric cancers.

Among 88,493 individuals under age 18 with a diagnosed congenital heart defect, the incidence of any neoplasm diagnosed at least 30 days after diagnosis of the heart defect was 3.91/1,000, compared with 0.79/1,000 in more than 6 million children and adolescents without congenital heart disease.

Thus, children with a congenital heart defect were at a 4.9-fold increased risk for developing a childhood cancer. The risk for bone tumors was 11.2-fold greater than in the general pediatric population, and their neuroblastoma risk was 9.8-fold greater. Their risks of lymphoma and leukemia were increased 5.2- and 2.8-fold, respectively. Of note, they had no increased risk of brain tumors.

To confirm their results, Dr. Oster and his coinvestigators also conducted a sensitivity analysis limited to the 55,079 children and adolescents with at least two outpatient or one inpatient ICD-9 diagnostic code for congenital heart disease. Here the incidence of childhood malignancies was 5.1/1,000 patients, for an overall 6.4-fold increased relative risk.

“Bedside-to-bench work is now needed to determine potential mechanisms,” he said. “We believe the increased risk is related more to a common genetic pathway than to an exposure or treatment pathway because it occurs so early. But there may be some impact of exposures or treatment as well. We think that radiation exposure is more of a longer-term risk.”

He and his coinvestigators next plan to look at the impact on pediatric cancer risk of specific types of congenital heart defects.

Dr. Oster reported having no financial conflicts of interest regarding this study, which received Centers for Disease Control and Prevention funding.

bjancin@frontlinemedcom.com

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