Collection of Autologous Peripheral Blood Stem Cells (PBSC): Safety Evaluations during the Peri-Apheresis Period.

Background. The collection of PBSC, mobilized after chemotherapy by the use of granulocyte colony-stimulating factor (G-CSF), is widely performed for autologous hematopoietic stem cell transplantation. However, the safety of this procedure has not yet been extensively evaluated. We investigated the safety of this procedure, focusing on the peri-apheresis period, by comparison to that in G-CSF-mobilized healthy donors for allogeneic hematopoietic stem cell transplantation.

Methods. We retrospectively analyzed our patient/donor database from January 2000 to December 2003. A total of 118 consecutive patients (73 males, 45 females) were compared with 258 healthy donors (135 males, 123 females). The patient group was significantly younger (median 30 y, range, 2-67 vs 45 y, 7–71) and weighed less (median 56 kg, 11.2–116.7 vs 60.5 kg, 25.7–115.0) than the normal donors. For autologous PBSC collection, patients were given chemotherapy followed by G-CSF 2-5μg/kg after myelosuppression, and leukapheresis was performed during the recovery phase. In the allogeneic setting, a healthy donor was given G-CSF 10μg/kg subcutaneously and leukapheresis was done on the 4^th - 6^th days. A Spectra (Gambro) or AS104 (Fresenius) cell separator was used for leukaphereis. Other conditions during apheresis, including processed blood volume (median 10 liters), time and volume of ACD solutions used, did not differ significantly between the two groups.

Results. The total/median numbers of leukapheresis per subject in the patient and the donor groups were 149/1.3 and 490/1.9, respectively. The frequency of symptoms and signs observed during leukapheresis, i.e. such as numbness, chill, nausea, vomiting, light headedness, dizziness, etc., was significantly less in the patient group than in the donor group (34.9% vs 47.1%, p<0.01), while the types and grades were similar. However, in the patient group, the degree of platelet loss after each leukapheresis procedure was significantly lower, and the platelet count recovered to above the pre-apheresis level on the next day without any add-back of platelet-rich plasma in all cases. The frequency of discontinued apheresis was similar; 4 (2.68%) in patients and 13 (2.65%) in donors. However, the reasons for such discontinuation in the patient group included shivering with chill, high fever, poor general condition and pale face, which might lead to serious events, whereas the primary cause in the donor group were vasovagal reflex and hypocalcemia due to anticoagulant. In patients, systolic blood pressure tended to fluctuate more and heart rates had remained higher than 90 per min throughout procedures, whereas the heart rate remained between 70 and 80 in donors.

Conclusions. There were unexpectedly fewer adverse events during the peri-apheresis period in patients than in healthy donors. Considering that patients had been ill and treated heavily, it is likely that they were more familiar with medical procedures and could cope better with stress. Nevertheless, it is presumed that they more easily became seriously ill because they were less stable with regard to their hemo-dynamics and general condition. We conclude that leukapheresis for autologous PBSC collection might carry a higher potential risk than in healthy donors, and careful monitoring and the application of appropriate guidelines are required, as in healthy donors.