The management of bilateral Wilms tumor.

Wilms tumor (WT) is the most common malignant renal tumor in childhood. Approximately 5-7% of WT patients present with bilateral disease, either synchronously or metachronously. Bilateral WT usually occurs in younger children and more often in girls. Management of a child with bilateral WT is very challenging. In contrast to unilateral WT, there has not been uniform agreement about the therapeutic strategy in the management of bilateral WT. As surgery is a critical component in the treatment of WT, the aim is to achieve a high cure rate while maintaining adequate long-term renal function in patients with bilateral WT. In the past, radical surgical procedures which lead to the patients on dialysis have been traditionally recommended in these patients. After several multicentre trials, bilateral biopsies followed by pre-operative chemotherapy and then renal salvage surgery have been recommended. The management of bilateral WT has evolved from primary surgical extirpation to kidney-preserving resection after preoperative chemotherapy. Preoperative chemotherapy often results in significant reduction in tumor size, thereby facilitating subsequent renal salvage. The analysis of children with bilateral WT shows that preservation of renal parenchyma is possible following initial preoperative chemotherapy. Only centers with experience in bilateral WT should treat the cases with bilateral WT to provide optimal treatment.