Within 6 weeks after induction chemotherapy, patients receive consolidation chemotherapy comprising carboplatin IV over 2 hours on days 0-1 followed immediately by escalating doses of thiotepa IV over 2 hours. Patients then undergo peripheral blood stem cell transplantation 48 hours after the last thiotepa dose. Patients receive G-CSF SC daily on days 3 to 21. Treatment repeats every 21 days for up to 3 courses in the absence of disease progression or unacceptable toxicity.