Prevalence of Beckwith Wiedemann Syndrome and Risk of Embryonal Tumors in Children Born with Omphalocele.

AIM OF THE STUDY:Children with omphalocele have an increased prevalence of Beckwith Wiedemann syndrome (BWS) and thus a suspected increased risk of developing embryonal tumors, e.g. Wilms tumor, hepatoblastoma, neuroblastoma and rhabdomyosarcoma. The aim of this study was to examine the prevalence of BWS and the risk of embryonal tumors amongst patients born with omphalocele. METHODS:A population-based cohort was used, including all children born in Sweden 1/1 1997-31/12 2016. Patients with omphalocele were identified through the Swedish National Patient Register and the Swedish Medical Birth Register. For each case of omphalocele ten age and sex matched individuals unexposed for omphalocele were randomly selected for comparison. Data on BWS and embryonal tumors were collected from the Swedish National Patient Register and the Swedish National Cancer Register. MAIN RESULTS:Out of 207 cases of omphalocele, 15 (7.2%) were diagnosed with BWS. None of the children with omphalocele had yet developed any kind of embryonal tumor (median follow-up time 8 years). None of the 2070 controls were diagnosed with BWS but 3 (0.1%) of them had developed embryonal tumors during a median follow-up time of 10 years. CONCLUSIONS:In this study the prevalence of BWS amongst children born with omphalocele is in the lower range of previously reported figures. Also, the prevalence of embryonal tumors amongst children with BWS is lower than expected and the risk of embryonal tumors in children with omphalocele and BWS might not be as high as previously stated. This must be taken into consideration when counseling parents prenatally. TYPE OF STUDY:National register cohort study. LEVEL OF EVIDENCE:II.