A comprehensive review of pediatric urachal anomalies and predictive analysis for adult urachal adenocarcinoma

Purpose: We examined the presentation, diagnosis and management of radiologically detected pediatric urachal anomalies and assessed the risk of malignant degeneration.

Materials and methods: Our radiology database (2000 to 2012) was queried for all children younger than 18 years who were diagnosed with a urachal anomaly radiographically, and the operative database was used to determine those who underwent excision. Data collected included demographics, presenting symptoms, imaging modality and indication for excision. These data were compared to the Ontario Cancer Registry to determine the risk of malignancy.

Results: A total of 721 patients were radiographically diagnosed with a urachal anomaly (667 incidentally), yielding a prevalence of 1.03% of the general pediatric population. Diagnoses were urachal remnants (89% of cases), urachal cysts (9%) and patent urachus (1.5%). Ultrasonography was the most common imaging modality (92% of cases), followed by fluoroscopy/voiding cystourethrography (5%) and computerized tomography/magnetic resonance imaging (3%). A total of 61 patients (8.3%) underwent surgical excision. Indications for imaging and treatment were umbilical drainage (43% of patients), abdominal pain (28%), palpable mass (25%) and urinary tract infection (7%). Mean age at excision was 5.6 years and 64% of the patients were male. Based on provincial data, the number needed to be excised to prevent a single case of urachal adenocarcinoma was 5,721.

Conclusions: Urachal anomalies are more common than previously reported. Children with asymptomatic lesions do not appear to benefit from prophylactic excision, as the risk of malignancy later in life is remote and a large number of urachal anomalies would need to be removed to prevent a single case of urachal adenocarcinoma.