Bilateral Wilms' tumor--surgical aspects.

Four to eight percent of all Wilms' tumors are bilateral. Achieving curative resection of such tumors by partial nephrectomy or tumor enucleation while maintaining sufficient renal function represents a surgical challenge. Effective preoperative chemotherapy facilitates this aim considerably. Seven patients who were diagnosed to have bilateral synchronous Wilms' tumors between 1990 and 1994 are being reviewed. At the time of initial diagnosis, their mean age was 24.4 months, range 7 to 45 months. In 4 cases, pre-operative imaging did not reveal the full extent of the lesions, and in one of these, involvement of the second kidney was only detected by surgical exploration. Five of the children received at least 4 weeks of neo-adjuvant chemotherapy without primary biopsy, followed by bilateral tumor resection. One child had to be operated on as an emergency without any preliminary treatment, and in one, chemotherapy was interrupted after 3 weeks because of veno-occlusive disease. After a follow-up period of 66 months on the average (range 50 to 81 months), five of the patients are free of recurrence and clinically well--one with a kidney graft. The remaining two patients have died. Discussion is focussed on different management strategies of this rather rare pathology considering SIOP und NWTS protocols.