- Unilateral Wilms tumor and aniridia, Beckwith-Wiedemann Syndrome, idiopathic hemihypertrophy, Simpson-Golabi-Behmel-Syndrome, Denys-Drash Syndrome or other associated genitourinary anomalies associated with bilateral Wilms tumor, such as hypospadias and undescended testis (to be eligible, these patients must not undergo any nephrectomy at diagnosis; note-horseshoe kidney is not associated with bilateral Wilms tumor and these patients should go on the appropriate unilateral Wilms tumor study); or