Patients receive thiotepa IV over 2 hours on days 0 and 1; topotecan IV over 30 minutes on days 0-4; and carboplatin IV over 2 hours on days 2 and 3. Patients also receive G-CSF beginning on day 5, 24-36 hours following the last dose of topotecan. PBSC are reinfused on day 6 (36-48 hours following the last dose of topotecan) of each course of therapy. Patients receive 3 courses of therapy.