Autologous peripheral blood stem cell transplantation using simplified procedures for collection and freezing

High-dose therapy with peripheral blood stem cell (PBSC) transplantation has been used increasingly for chemosensitive malignancies. The conventional procedures for collection and freezing of PBSCs are time-consuming and expensive. The optimal conditions for priming, collection and freezing of PBSCs have yet to be simplified.

Simplified procedures for mobilization, collection and freezing were developed to provide PBSC transplantation. Twenty-two cancer patients were given intensive chemotherapy with a variety of regimens using granulocyte-colony stimulating factor (G-CSF, filgrastim) 300 micrograms/d subcutaneously to mobilize PBSCs. A rapidly rebounding white blood cell (WBC) count from nadir was used to predict the time of peak PBSC release and plan leukapheresis. Leukapheresis was performed, when the WBC count was greater than 1.0 x 10(9)/l.

Leukapheresis was performed in all 22 patients on day 10 to 14 after completing intensive chemotherapy. G-CSF to mobilize PBSCs was administered for a median of 10 days (range, 7-12 days). Twenty-one of 22 patients achieved the target yield of greater than 2 x 10(6) CD34+ cells/kg of body weight (BW). This was achieved in a median of two harvests (range, 2-4), with a median processed blood volume of 10.2 l/apheresis. A median of 6.4 x 10(8) mononuclear cells/kg BW and 5.2 x 10(6) CD34+ cells/kg BW for each patient were obtained. After high-dose cancer chemotherapy and PBSC transplantation, rapid and sustained hematopoietic engraftment occurred in all but one patient who had an inadequate number of CD34+ cells. In patients with an adequate target yield of CD34+ cells, the median times to achieve an absolute neutrophil count of greater than 0.5 x 10(9)/l and a platelet count of greater than 20 x 10(9)/l were nine days (range, 7-12 days) and 12 days (range, 8-14 days), respectively.

Adequate PBSCs can be achieved within a median of two aphereses in most eligible cancer patients. Apheresis should be performed on day 10 to 14 after completing intensive chemotherapy, followed by G-CSF 300 micrograms/d. This simple and effective approach makes PBSC transplantation more practicable for a wider range of malignant diseases.