OBJECTIVES: I. Determine the complete and partial response rate of patients with relapsed or refractory B-cell non-Hodgkin's lymphoma treated with rituximab and high-dose carmustine, etoposide, cytarabine and melphalan followed by autologous bone marrow or peripheral blood stem cell transplantation. II. Determine the toxicity profile of this regimen in these patients. III. Compare the levels of soluble CD20 antigen and rituximab blood levels with patient outcomes in this patient population.

OUTLINE: Patients receive two doses of rituximab IV over 3-4 hours 1 week apart. Stem cells from the peripheral blood or bone marrow are collected at least 1 week after the second dose of rituximab. Following stem cell collection, patients receive a third dose of rituximab IV as above between days -10 and -6. Patients then receive high-dose chemotherapy consisting of carmustine IV on day -6, etoposide IV twice daily and cytarabine IV on days

• 5 to -2, and melphalan IV on day -1. On day 0 patients undergo autologous bone marrow or peripheral blood stem cell transplantation. After transplantation, patients receive a fourth dose of rituximab as above at approximately day 30, and then weekly over 4 weeks at approximately 6 months in the absence of disease progression or unacceptable toxicity. Patients are followed at 1 year and then annually thereafter.

PROJECTED ACCRUAL: A total of 23-40 patients will be accrued for this study within 3 years.