Stem cell mobilization in resistant or relapsed lymphoma: superior yield of progenitor cells following a salvage regimen comprising ifosphamide, etoposide and epirubicin compared to intermediate-dose cyclophosphamide

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 mu g/d). Patients were mobilized with one of two chemotherapy regimens, either cyclophophamide (3 g/m(2) or 4 g/m(2)) (n=50) or ifosphamide, etoposide and epirubicin (IVE: n=16). The target of collecting >2.0x10(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 (8.62x10(6)/kg) compared with cyclophosphamide plus G-CSF (3.59x10(6)/kg) (P=0.045). The median yield of CD34(+) cells per leukapheresis was almost twice as high in patients receiving IVE (1.94x10(6)/kg) compared to cyclophosphamide (1.03x10(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.