Patients receive ifosfamide intravenously (IV) continuously over days 1-4, vinorelbine tartrate IV over 6-10 minutes on days 1 and 5, and bortezomib intravenously on days 1, 4, and 8, and filgrastim (G-CSF) by vein or subcutaneously beginning on day 6 and continuing until blood counts recover or peripheral blood stem cells (PBSC) are harvested. Treatment cycles repeat every 21 days for up to 2 or 4 courses in the absence of disease progression or unacceptable toxicity.