To prospectively analyze factors that influence peripheral blood stem cell (PBSC) collection and hematopoietic recovery after high-dose chemotherapy (HDC), 39 patients received cyclophosphamide 4 g/m2 and rHuG-CSF (Filgrastim) 5 μg/kg/day. Leukapheresis was started when CD34+ cells/mL were > 5 x 103. A minimum of 2 x 106 CD34+ cells/kg was collected. Median steady-state bone marrow CD34+ cell percentage was 0.8% (range, 0.1 to 6). Thirty-two patients received HDC with autologous PBSC transplantation plus Filgrastim. A median of 2 (range, 0 to 6) leukapheresis per patient were performed and a median of 6.3 X 106 CD34+ cells/kg (range, 0 to 44.4) collected; four patients failed to mobilize CD34+ cells. The number of cycles of prior chemotherapy had an inverse correlation with the number CD34+ cells/kg collected (r = -0.38; p < 0.005). Patients with < 7 cycles had a higher predictability for onset of leukapheresis than patients with 37 (93% versus 50%; p < 0.005). The four patients who failed to mobilize had received ≥ 7 cycles. The number of CD34+ cells/kg infused after HDC had an inverse correlation with days to recovery to 0.5 x 109 neutrophils/L and 20 x 109 platelets/L (r = -0.68 and -0.56; p < 0.005). The effect of these factors on mobilization and hematopoietic recovery were confirmed by multivariate analysis. Requirements for supportive measures were significantly lower in patients given a higher dose of CD34+ cells/kg. Therefore, PBSC collection should be planned early in the course of chemotherapy. Larger number of CD34+ cells/kg determined a more rapid hematopoietic recovery and a decrease of required supportive measures.
- Hematopoietic recovery
- Peripheral blood stem cell mobilization
- Supportive requirements