Imaging, radiation exposure, and attributable cancer risk for neonates with necrotizing enterocolitis

Neonates with necrotizing enterocolitis (NEC) receive numerous radiologic investigations that potentially increase their lifetime cancer mortality risk. We evaluated our radiologic practice pattern for patients with NEC and estimated cumulative radiation exposure and lifetime cancer risk.

Infants with NEC in a tertiary care NICU had patient demographics, imaging, treatments/interventions, and outcomes analyzed over 3 years. The number and type of imaging were recorded, including NEC-related imaging (thoraco-abdominal "babygrams" and abdominal radiographs), and all other imaging modalities. Patients were stratified by birth weight: group 1 (<750 g); group 2 (751-1500 g); and group 3 (>1501 g). Pre-existing normative data were used to calculate radiation exposure, absorption, and attributable cancer risk from NEC-related imaging.

Sixty-four neonates with 72 episodes of NEC were identified. Overall survival was 75.0%. When stratified by birth weight, mean abdominal radiographs and babygrams comprised 51%, 60%, and 74% of total imaging, giving median mGy doses of 2.1, 0.4, and 0.2, respectively. Compared to normative data, radiation dosing, and median cumulative cancer lifetime mortality risk increased by an average of 4.3× from baseline, with two cases documenting a 20-fold increase.

Neonates with NEC are exposed to significant amounts of radiation directly attributable to disease surveillance. Non-radiologic surveillance methods could significantly reduce radiation exposure and cancer risk in these infants.