Ifosfamide, epirubicin, and etoposide (IEV) mobilize peripheral blood stem cells more efficiently than cyclophosphamide/etoposide

High-dose chemotherapy with autologous stem cell support is an effective treatment in advanced multiple myeloma. In this study, we compare chemotherapy with ifosfamide, epirubicin, and etoposide (IEV) or cyclophosphamide and etoposide (CE) in 47 patients with multiple myeloma with regard to stem cell mobilization, toxicity, and tumor response. The proportion of patients reaching the threshold of >6 × 10⁶ CD34⁺ cells/kg body weight was significantly higher in the IEV group (97% vs 71%), and more CD34⁺ cells (10 × 10⁶ vs 3.5 × 10⁶ cells/kg; p = 0.002) could be collected by the first leukapheresis associated with less leukaphereses needed. Non-hematopoietic side effects were mild with nausea being more frequent after IEV treatment (30% vs 7%). Grade 3/4 neutropenia (thrombocytopenia) occurred in 89 and 100% (55 and 44%) of the patients. There was one treatment-related death due to septic shock in the IEV group. Grade 3/4 anemia was more frequent in the IEV group (19% vs 0%). Forty-two percent (IEV) and 50% (CE) received inpatient treatment for neutropenic fever. In 20 and 7% of the patients, a partial response was observed after IEV and CE. However, the overall response rate (complete response and partial tumor response) after mobilization and tandem high-dose chemotherapy was 75% after IEV and 78% after CE and, thus, independent of the mobilization. In summary, both treatment protocols can readily be used for the mobilization of peripheral blood stem cells with comparable major toxicities and similar tumor response rates. However, the efficiency of the stem cell mobilization was significantly higher after IEV treatment.