Margin status and tumor recurrence after nephron-sparing surgery for bilateral Wilms tumor

PurposeNephron-sparing surgery (NSS) has been advocated for patients with bilateral Wilms tumor (BWT). We sought to determine whether margin status impacted local tumor recurrence.MethodsA retrospective review of patients undergoing NSS for BWT from November 1999 to March 2009 at our institution in which local recurrence rates based on margin status were compared.ResultsOf 21 patients, five (23.8%) had positive margins. These and 2 (9.5%) with focal anaplasia received flank XRT. Seven (33%) patients developed recurrent disease, a mean of 18.0 (range 1.3-39.9) months after NSS. Recurrence rates were similar in patients with positive and negative margins (1/5 [20%] vs 6/16 [37.5%]; p = 0.47). Hypertension occurred more frequently in patients who received XRT (57.1% vs 28.6%). At a median follow-up of 28.6 months (range 5.2-142.3), 19 patients are alive, without evidence of disease; one patient (with a positive margin at initial NSS) died of metastatic anaplastic WT and another died of a brain tumor. One patient, with multiple risk factors, developed renal failure.ConclusionsIn our experience, local recurrence rates after NSS were not affected by surgical margin status although all patients with positive margins received XRT. These results support the aggressive use of NSS for patients with BWT.