Fibroepithelial polyps causing ureteropelvic junction obstruction in children.

PURPOSE: Fibroepithelial polyps are benign mucosal projections that can be found throughout the urinary system. We review our experience with fibroepithelial polyps of the ureteropelvic junction in children to define more clearly this entity and its outcome following treatment.
METHODS: We reviewed the records of all children with fibroepithelial polyps causing ureteropelvic junction obstruction treated at our institution between December 1967 and February 2002.
RESULTS: Nine patients 6 weeks to 9 years old had 11 ureteropelvic junction obstructions secondary to fibroepithelial polyps, representing a 0.5% incidence of all ureteropelvic junction obstructions seen during that period. The majority of the patients were male (89%) and had obstruction on the left side (78%). Only 22% of the patients had a diagnosis of obstructing polyps suggested preoperatively. All patients underwent dismembered pyeloplasty but 1 required subsequent nephrectomy due to progressive loss of renal function. All lesions were characterized microscopically by polypoid projections of fibrous tissue covered by epithelium and demonstrating varying degrees of inflammation. No recurrences were seen during a mean followup of 44 months.
CONCLUSIONS: Fibroepithelial polyps are rare lesions that cause ureteropelvic junction obstruction in children, primarily in males and on the left side. Filling defects were diagnosed preoperatively in 22% of the patients in this series. Excision and dismembered pyeloplasty were curative, and recurrences were not observed. The etiology of this disease remains obscure.