To demonstrate the non-inferiority of 6 weeks of preoperative chemotherapy with VCE compared to chemotherapy with AVD based on the early overall metastatic response rate (MetRR) in newly diagnosed stage 4 paediatric renal tumours (equivalence test). The MetRR includes the pulmonary response rate (PRR) and the non-pulmonary metastatic response rate (NPRR).
The entire clinical trial comprises the 6-week preoperative therapy. This is followed by observation of further treatment, which usually lasts 29 weeks (2 weeks perioperative phase and 27 weeks of therapy).