We analysed the factors influencing the efficacy of peripheral blood stem cell (PBSC) collection in patients with lymphoma. Sixty-six patients underwent initial PBSC collection following mobilization with chemotherapy plus recombinant granulocyte colony-stimulating factor (300 microg/d). Patients were mobilized with one of two chemotherapy regimens, either cyclophophamide (3 g/m2 or 4 g/m2) (n = 50) or ifosphamide, etoposide and epirubicin (IVE; n = 16). The target of collecting > 2.0 x 10(6) CD34+ cells/kg was achieved in 43/66 (65%) patients with a median of two apheresis procedures. The IVE plus G-CSF mobilization regimen gave a significantly higher median yield of CD34+ cells (8.62 x 10(6)/kg) compared with cyclophosphamide plus G-CSF (3.59 x 10(6)/kg) (P = 0.045). The median yield of CD34+ cells per leukapheresis was almost twice as high in patients receiving IVE (1.94 x 10(6)/kg) compared to cyclophosphamide (1.03 x 10(6)/kg) (P = 0.035). In a univariate analysis of the factors affecting mobilization, the subtype of lymphoma (high-grade NHL) and the mobilization regimen were the only factors associated with high CD34+ cell yield. However, in a multivariate analysis of factors affecting mobilization including age, lymphoma subtype, previous chemotherapy and radiotherapy, only the use of the IVE protocol was predictive of a high yield of CD34+ cells. In 13 patients undergoing a second mobilization procedure the use of IVE was associated with a significantly higher yield of CD34+ cells compared to cyclophosphamide; three patients who failed cyclophosphamide plus G-CSF mobilization were able to proceed to transplantation following successful mobilization with IVE + G-CSF. These results demonstrate that IVE is a highly effective mobilization regimen which is superior to cyclophophamide and has the benefit of being effective salvage therapy for lymphoma patients.