Peripheral blood progenitor cell mobilization with Dexa-Beam/G-CSF, ether lipid purging, and autologous transplantation after high-dose CBV treatment: a safe and effective regimen in patients with poor risk malignant lymphomas.

High-dose chemotherapy followed by autologous peripheral blood progenitor cell transplantation (PBPCT) is increasingly applied in patients with relapsed, poor risk malignant lymphomas. Different strategies for progenitor cell mobilization using cytoreductive chemotherapy, hematopoietic growth factors, or both have been described. We studied the safety and efficacy of a modified DexaBEAM regimen (dexamethasone, BCNU [carmustine], etoposide, ara-C, melphalan) followed by granulocyte-colony stimulating factor (G-CSF) that was administered in order to minimize any residual disease and to obtain a sufficient amount of progenitor cells in the autografts. Until now, 16 patients at poor risk (8 with Hodgkin's disease, 8 with non-Hodgkin's lymphoma) entered the study. All the 12 patients with measurable disease at study entry responded to DexaBEAM. Median time of subsequent leukopenia (leukocytes < 1.000/microL) was 6 days (range 5-8 days). Peak numbers of CD34+ hematopoietic progenitor cells appeared in the peripheral blood after a median of 20 days (range 18-22 days) after onset of therapy. At that time, peripheral mononuclear cells were collected for autografting. Thereafter, the leukapheresis products were frozen until the day of transplantation, either unpurged in the case of Hodgkin's disease or purged with the ether lipid edelfosine in cases of non-Hodgkin's lymphoma. After high-dose chemotherapy with the CBV regimen (cyclophosphamide, BCNU, etoposide) the patients received their autografts, followed again by G-CSF treatment. A stable hematopoietic recovery was reached with granulocytes > 2.000/muL within 11 days (range 8-17 days), and platelets > 50.000/microL within 15 days (range 10-31 days), respectively, without significant differences between the purged and unpurged transplants. After a median follow-up of 28 months (range 1-40 months) 7 patients are alive without signs of recurrent disease, while 1 patient has died due to acute treatment related toxicity. Three patients had refractory disease, and 5 have relapsed of whom 4 have died. In summary, the DexaBEAM/G-CSF/CBV strategy appears to be safe and effective for salvage treatment in patients with poor risk malignant lymphomas.