RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. It is not yet known which regimen of chemotherapy is more effective for stage I Wilms' tumor.

PURPOSE: Randomized phase III trial to study the effectiveness of chemotherapy and surgery in treating children who are at risk of or who have stage I Wilms' tumor.

OBJECTIVES: I. Determine the initial extension of disease, surgical procedures, gross and histological morphology, treatments, clinical outcome, and late consequences of therapy after treatment with neoadjuvant chemotherapy, surgery, and adjuvant chemotherapy with or without maintenance chemotherapy in patients with intermediate risk or anaplastic stage I Wilms' tumor. II. Determine the safety and effectiveness of reduced chemotherapy in these patients.

OUTLINE: This is a randomized, multicenter study. Patients receive dactinomycin IV on days 1-3 and 15-17 and vincristine IV on days 1, 8, 15, and 22. Patients then undergo surgery about a week after completion of chemotherapy. After surgery, patients receive vincristine IV on days 1, 8, 15, and 22 and dactinomycin IV on days 8-12. Patients are then randomized to one of two treatment arms after week 9. Arm I: Patients receive dactinomycin IV on days 1-5 of week 10 and vincristine IV on day 1 of both weeks 10 and 11. This course is repeated during weeks 17 and 18. Arm II: Patients receive no further treatment. Patients are followed every 3 months for 3 years, then annually thereafter. Peer Reviewed and Funded or Endorsed by Cancer Research UK

PROJECTED ACCRUAL: A total of 350 patients (175 per treatment arm) will be accrued for this study within 7-8 years.

DISEASE CHARACTERISTICS: Initial diagnosis of a unilateral tumor with clinical and radiological characteristics of a nephroblastoma Histologically proven stage I Wilms' tumor after neoadjuvant treatment and surgery Intermediate risk or anaplastic No detectable distant metastases 4 weeks after adjuvant chemotherapy

PATIENT CHARACTERISTICS: Age: 0.5 to 17 Performance status: Not specified Life expectancy: Not specified Hematopoietic: Not specified Hepatic: Not specified Renal: Not specified

PRIOR CONCURRENT THERAPY: See Disease Characteristics