See “Radiation Exposure and Attributable Cancer Risk in Patients With Esophageal Atresia” by Yousef and Baird on page 234.
In their article, Yousef and Baird (1) call our attention to the potential danger of overirradiating children with esophageal atresia (EA) during the neonatal period. This is an important message—for an audience not limited to neonatologists and surgeons—that should be read in detail by all teams, including pediatric gastroenterologists, working with neonates presenting with medical-surgical digestive diseases (ie EA, gastroschisis, short bowel syndrome, diaphragmatic hernia, necrotizing enterocolitis) who will need successive and numerous imaging. As concluded by the authors, all efforts should be made to reduce irradiation burden and to instead use nonirradiating methods (eg, ultrasound, magnetic resonance imaging, endoscopy). Finally, they question the practice of ALARA (As Low As Reasonably Achievable) principles in centers caring for patients with neonatal digestive diseases.
The authors chose a specific group of patients with EA who could be considered one of the highest risk groups for neonatal irradiation. Indeed, due to the complexity of their surgical repair and the high prevalence of complications (ie, esophageal stricture, leak, recurrent fistula, tracheomalacia, gastroesophageal reflux) children with EA undergo substantial numbers of imaging studies for diagnostic and therapeutic procedures (2). The authors show that these patients are exposed to a significant increase in irradiation and conclude that this leads to a 130-fold increase in their risk of developing cancer later in life. This is a clear warning, but to be definitive a much longer follow-up is needed.
Controversial data on this topic have been published previously. In their article, Puch-Kapst et al (3) showed that neonatal intensive care unit-treated very-low-birth-weight infants had lower radiation exposure compared to annual natural background radiation levels. Baird et al (4) showed that neonates with necrotizing enterocolitis are exposed to significant amounts of radiation, that this is attributable to disease surveillance, and that their median cumulative lifetime mortality risk from cancer is therefore increased by an average of 4.3. Sources of radiation include conventional x-ray (eg, plain radiography, opacification) and computed tomography (CT) scan. Although not assessed in the study by Yousef and Baird, the level of pediatric radiation exposure from CT scans also remains a matter of debate (5,6).
As acknowledged by the authors, there are limitations to their study (as there are with most of those previously published). The first limitation is the study's retrospective nature, which led them to include excessive radiation exposure due to use of older equipment that is greatly reduced by modern equipment. The second limitation is the relatively short duration of follow-up and lack of data confirming the long-term health consequences of irradiation. There is currently no evidence for increased cancer risk in the EA population, aside from concern about esophageal cancer (of which there have been 8 cases reported in patients with EA); furthermore, this is not a classic cancer due to irradiation (ie, it is predominantly brain cancer and leukemia), but is instead caused by severe gastroesophageal reflux disease, esophageal dysmotility or lesion (2).
Indeed, it is currently impossible to predict whether an individual will experience the consequences of radiation (6). Another problem is related to the calculation of risk. Authors usually choose previously published radiation data or data supplied by the International Commission on Radiologic Protection as references for studies, because it has been shown that estimating radiation exposure and cancer risk may be inexact (6).
Avoiding unnecessary irradiation in patients with EA should be a concern for the multidisciplinary team: routine contrast studies 7 days postoperatively should be questioned; standardization and optimization of techniques (eg, x-ray beam intensity and collimation, limiting area of exposure) should be preferred; systematic, routine x-ray should be abandoned; and magnetic resonance imaging should be preferred over CT scan when required. In respect to pediatric gastrointestinal problems, the main radiation sources are contrast esophagram and upper gastrointestinal study. Endoscopy is an alternative (ie, for diagnosing anastomotic stenosis) (2) but has its own disadvantages and constraints.
In conclusion, these authors are to be congratulated for their excellent work, which should lead to dramatic modifications in our approach to surveillance of newborns with EA and other neonatal digestive diseases. Potential radiation risk, including developing cancer, is one more reason to follow these patients long-term, through adulthood (2).
1. Yousef Y, Baird R. Radiation exposure and attributable cancer risk in patients with esophageal atresia. J Pediatr Gastroenterol Nutr
2. Krishnan U, Mousa H, Dall’Oglio L, et al. ESPGHAN-NASPGHAN guidelines for the evaluation and treatment of gastrointestinal and nutritional complications in children with esophageal atresia-tracheoesophageal fistula. J Pediatr Gastroenterol Nutr
3. Puch-Kapst K, Juran R, Stoever B, et al. Radiation exposure in 212 very low and extremely low birth weight infants. Pediatrics
4. Baird R, Tessier R, Guilbault MP, et al. Imaging, radiation exposure, and attributable cancer risk for neonates with necrotizing enterocolitis. J Pediatr Surg
5. Miglioretti DL, Johnson E, Williams A, et al. The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk. JAMA Pediatr
6. Arthurs OJ, Bjorkum AA. Safety in pediatric imaging: an update. Acta Radiol