VAD REGIMEN (stage I-IV bilateral Wilms tumor [BWT] with biopsy revealing favorable histology or no preoperative biopsy; stage I-III BWT with focal anaplasia; stage I BWT with diffuse anaplasia; or high-risk, stage III-IV unilateral Wilms tumor [WT] with contralateral nephrogenic rest [NR] or predisposition syndrome): Patients receive vincristine sulfate intravenously (IV) over 1 minute on days 1, 8, 15, 22, 29, and 36 (weeks 1-6) and dactinomycin IV and doxorubicin hydrochloride IV over 15-120 minutes on days 1 and 22 (weeks 1 and 4).