Immediate nephrectomy versus preoperative chemotherapy in the management of non-metastatic Wilms' tumour: results of a randomised trial (UKW3) by the UK Children's Cancer Study Group.

Purpose: To determine if patients receiving preoperative chemotherapy with vincristine and actinomycin D for non-metastatic Wilms' tumour have a more advantageous stage distribution and so need less treatment compared to patients who have immediate nephrectomy, without adversely affecting outcome.

Methods: Between 1991 and 2001, a total of 205 patients with newly diagnosed non-metastatic renal tumours, of which 186 had Wilms' histologies, were randomly assigned either to immediate surgery or to 6 weeks preoperative chemotherapy and then delayed surgery. Both groups of children received postoperative chemotherapy according to tumour stage and histology determined at the time of nephrectomy.