A phase I/II study was performed to analyse the ability of ifosfamide-based chemotherapy with rituximab to produce a turmour-free graft as well as the safety of retuximab prior to stem cell harvest and post high-dose chemotherapy. Twenty-two patients with B-cell non-Hodgkin's lymphoma were enrolled either having aggressive large-cell disease in relapse or at high/high-intermediate risk of relapse, or refractory lymphoma or mantle cell lymphoma, or indolent lymphoma. Chemotherapy consisted of ifosfamide 2 g/m2, days 1-3 with mesna, etoposide 100 mg/m2, days 1-3, and mitoxantrone 8 mg/m2 day 1, with figrastim. Rituximab was given at 375 mg/m2 for 4 doses. An encouraging overall response rate of 90%, including 11 CRs was achieved. CD34+ cells were successfully mobilized in 18 or 19 patients analysed so far with a median number of 3.4 x 10(6) cells/kg. The combination of ifosfamide-based chemotherapy with rituximab significantly reduced the number of contaminating B-cells in the stem cell product and so far there has only been a single relapse post high-dose chemotherapy with autologous haematopoietic transplant. The RIME regimen was generally well tolerated with minimal non-haematological toxicity and most of the treatment was done completely on an outpatient basis. Haematological toxicity was manageable with filgrastim, there were some infectious complications.