COMBINED CHEMOTHERAPY AND GRANULOCYTE-COLONY-STIMULATING FACTOR (G-CSF) MOBILIZE LARGE NUMBERS OF PERIPHERAL-BLOOD PROGENITOR CELLS IN PRETREATED PATIENTS

The aim of this study was to examine the effect of G-CSF given after salvage chemotherapy on the mobilisation of peripheral blood progenitor cells (PBPC) in pretreated patients. Seven patients with relapsed or refractory non-Hodgkin's lymphoma (NHL) were treated with methotrexate, cyclophosphamide, cytarabine, etoposide and dexamethasone. G-CSF was given at a dose of 3.8-7.2 mu g/kg (1-2 ampoules) daily by subcutaneous injection from the onset of neutropenia (<1.0 x 10(9)/L). A median of 3 leukaphereses was performed when the white cell count was recovering. The median number of granulocyte-macrophage colony-forming cells (GM-CFC) collected was 99 x 10(4)/kg per leucapheresis (range 19-800) or 260 x 10(4)/ kg in total per patient (110-1800). Six patients underwent myeloablative chemotherapy with PBPC rescue. No autologous bone marrow or growth factors post-PBPC infusion were administered. The median duration of severe neutropenia (<0.5 x 10(9)/L) was 8.5 days (range 5-10) and to recovery of neutrophils post-PBPC infusion was 11.5 days (10-15). Severe thrombocytopenia (<20 x 10(9)/L) was present for 4 days (range 1-5) and the median number of days post-infusion to platelet-transfusion independence was 9 (6-12). In conclusion, G-CSF combined with chemotherapy mobilised large numbers of PBPC for subsequent autotransplantation in pretreated patients with NHL. A single leukapheresis procedure may be sufficient following this protocol.