 PATIENT CHARACTERISTICS: Age: 45-60 Patients 10-45 are eligible for EORTC-06863 Performance status: Not specified Hematopoietic: Not specified Hepatic: No severe concomitant hepatic disease Renal: No severe concomitant renal disease Cardiovascular: No severe concomitant cardiac disease Other: No severe concomitant neurological disease No other progressive malignant disease 