Nephron sparing surgery for unilateral wilms tumor in children with predisposing syndromes: Single center experience over 10 years

Purpose: Unilateral Wilms tumors associated with predisposing syndromes are treated with preoperative chemotherapy followed by surgical resection. We describe our experience with nephron sparing surgery for Wilms tumor in this population at risk for metachronous lesions. Materials and Methods: We conducted a retrospective review of all children with a predisposing syndrome who underwent nephrectomy for malignancy during a 10-year period (2000 to 2010). Data collected included age, mode of detection, tumor size, treatment, pathology results, followup time and recurrence episodes. Results: From 2000 to 2010, 13 of 75 (19%) patients treated for Wilms tumor were diagnosed with predisposing syndrome(s). Eight patients with unilateral tumors were treated and had a mean age at diagnosis of 27 months (range 7 months to 9 years). Beckwith-Wiedemann syndrome, isolated hemihyperplasia, WAGR (Wilms tumor, Aniridia, Genitourinary abnormalities, mental Retardation) syndrome and isolated 11p13 deletion were the underlying diagnoses in 3, 2, 2 and 1 patient, respectively. All but 2 patients were diagnosed by screening ultrasound and 5 underwent preoperative chemotherapy. Median tumor size at surgery was 2.5 cm (range 1 to 13). Nephron sparing surgery was performed in 6 of 8 patients. Pathological study showed favorable histology Wilms tumor and nephrogenic rests in 6 and 2 patients, respectively. After a mean followup of 36 months (range 6 to 72) no recurrences were documented and all children had normal creatinine levels. Conclusions: Nephron sparing surgery appears safe for patients with unilateral Wilms tumor associated with predisposing syndrome(s), allowing for the preservation of renal function and good oncologic outcomes for the available followup time. If more studies confirm our observation, current recommendations for the surgical treatment of Wilms tumor may need to reemphasize the value of attempting nephron sparing surgery in this patient population.