Abstract 20252: Exposure to Low-Dose Ionizing Radiation From Cardiac Procedures and Risk of Malignancy in Adults With Congenital Heart Disease
Introduction: We showed that congenital heart disease (CHD) patients were exposed to increasing number of low-dose ionizing radiation (LDIR) from cardiac procedures between 1990 and 2005. We also showed an increase in prevalence of cancer among the adults with CHD (ACHD) in Quebec relative to the general population.
Hypothesis: This study aimed to measure the association between LDIR exposure and cancer incidence in ACHD patients.
Methods: We performed a nested case-control study using the Quebec CHD Database. Incident cancer cases were identified as the first cancer hospitalization from 1995 to 2010 (5-year wash-out period). Each case was matched on age, sex and calendar year with 4 controls. LDIR exposure was measured as lifetime cumulative number of LDIR cardiac procedures (cardiac catheterization, computed tomography scans of the chest, nuclear medicine and arrhythmia-related) prior to incident cancer diagnosis for each case-control pair.
Results: A total of 2690 cancer cases were matched with 10748 controls. Genitourinary, digestive, respiratory, breast and hematological cancers were accounted for 88.2% of cancers. In a restricted population of 2052, 18-65 year olds (median age=53, IQR 43,60) with specified CHD diagnoses, each additional LDIR procedure exposure was associated with 1.1-fold (95%CI: 1.1-1.2) increase in cancer risk. The impact of LDIR exposure as a categorical variable using conditional logistic regression is shown using patients with 0 or 1 procedures as reference. A sensitivity analysis in those with hematological cancers revealed an 6.3-fold (95%CI: 1.9-21.1) increase in cancer incidence related to ≥ 6 procedures.
Conclusions: We demonstrated an association between increase in exposure to LDIR-cardiac procedures and incident cancer risk in this population-based ACHD cohort. Studies are required to further understand this possible risk and to confirm these important findings in additional data sources.
Author Disclosures: S. Cohen: None. A. Liu: None. M. Gurvitz: None. E. Goossens: None. L. Guo: None. J. Therrien: None. A. Marelli: None.
- © 2016 by American Heart Association, Inc.