Background/purpose: Bilateral Wilms' tumors present a therapeutic challenge, particularly with delay in presentation, when there is poor response to chemotherapy and when associated with nephroblastomatosis. The primary aim of management is eradication of neoplasm, while at the same time preserving of renal function.
Methods: Nineteen bilateral Wilms' tumors were seen in our service between 1981 and 2003. This represented 10% of the 190 patients with Wilms' tumors seen during this period. There were 12 female and 7 male patients ranging in age from 7 months to 8 years. Fourteen had synchronous presentation, one of whom had liver metastasis at diagnosis. Of the 5 patients with metachronous tumors, 3 had their initial nephrectomies done elsewhere. Nephroblastomatosis was identified in 18 (95%) of the patients. Treatment was, in most cases, according to National Wilms Tumor Study Group protocols, with initial bilateral biopsy, neoadjuvant chemotherapy, and tumorectomy. Where indicated, nephrectomy (partial or complete) involved using ice dam topical cooling and vascular control, and in one case, bench surgery and extensive renal reconstruction with orthotopic autotransplantation. Revision tumorectomy was used on 3 occasions for recurrence in areas of nephroblastomatosis. There were 6 extrarenal relapses.
Results: Ten patients are alive and free of disease 1 to 15 years after treatment, all with well preserved renal function (lowest recorded glomerular filtration rate was 85 mL/min per 1.73 m2). Nine have died (2 of unrelated disease), including 6 of the 7 with spread outside the kidney. All 3 with unfavorable histology are alive. Of the 5 with metachronous presentations, 4 are alive, as are 7 of 10 who presented in the last decade.
Conclusions: Appropriate chemotherapy and conservative nephron-sparing and innovative surgery can achieve good results with preservation of adequate renal function in nearly all cases. Nephroblastomatosis was an almost universal finding and requires close monitoring because Wilms' tumors developed in residual suspect areas. Revision surgery was effective. Unfavorable histology did not have a reduced survival in our series. Metastatic spread outside the kidney had a poor prognosis.