Screening for Wilms tumor in children with Beckwith-Wiedemann syndrome or idiopathic hemihypertrophy

Background. Children with Beckwith-Wiedemann syndrome and idiopathic hemihypertrophy (BWS/HH) are at increased risk for developing Wilms tumor and screening with abdominal sonography is frequently recommended. However, there is a paucity of published data supporting this strategy. The purpose of this study was to determine whether sonographic screening at intervals of 4 months or less reduced the proportion of late-stage Wilms Tumor (WT) in children with BWS/HH. Procedure. A case series analysis was employed to compare the proportion of late-stage (stage III or IV) Wilms tumor in patients with BWS/HH who were screened with sonography (n = 15) to the proportion of late- stage Wilms tumor in unscreened patients with BWS/HH (n = 59). Patients were identified from the BWS Registry and from previously published studies. Screened patients had sonograms at intervals of 4 months or less. Results. None of the 12 screened children with Wilms tumor had late-stage disease, whereas 25 of 59 (42%) of unscreened children had late-stage Wilms tumor, a difference that was statistically significant (P < 0.003). Three children had false positive screening studies. They were operated on for suspected Wilms tumor but the lesions proved to be complicated renal cysts (n = 2) or nephroblastomatosis (n = 1). Conclusions. This study suggests that children with BWS/HH may benefit from screening sonograms at intervals of 4 months or less. However, false positive screening exams may result in unnecessary surgery. Given the rarity of BWS/HH, a larger, prospective international screening study is necessary to determine if the benefits of screening outweigh the risks.