OBJECTIVES: I. Compare the progression-free and overall survival of patients with relapsed or refractory, CD20 expressing, aggressive, B-cell non-Hodgkin's lymphoma treated with ifosfamide, carboplatin, and etoposide with or without rituximab. II. Compare the unconfirmed response rate of patients treated with these regimens. III. Determine the toxicity of ifosfamide, carboplatin, and etoposide with rituximab in these patients.