Ureteral Extension of Cystic Childhood Renal Tumors: A Case Series and Review of Literature.

Ureteral extension of childhood renal tumors is exceedingly rare. Hematuria, hydronephrosis, poorly or nonfunctioning kidney should raise suspicion for ureteral tumor extension. Identifying ureteral extension on preoperative imaging or intraoperatively before ureteral transection is crucial to obtain good oncological outcome without unnecessary exposure to radiation therapy or more intensive chemotherapy. In this report, we present three children with cystic renal tumors extending into the ureter and review the relevant literature.