Factors influencing the collection of peripheral blood stem cells in patients with acute myeloblastic leukemia and non-myeloid malignancies

Factors influencing the collection of autologous peripheral blood stem cells (PBSCs) were studied in 182 mobilization procedures performed on 145 consecutive patients with acute myeloblastic leukemia (AML; n=67) and with various non-myeloid malignancies (NMM; n=78). PBSC were collected following mobilization with chemotherapy, treatment with granulocyte colony-stimulating factor (G-CSF) or chemotherapy plus G-CSF. Fewer colony-forming unit granulocyte-macrophages (CFU-GMs) were collected from patients with AML than from patients with NMM (P<0.0001), although there were no differences in the numbers of CD34+ cells collected between both groups. Multiple regression analysis showed that chemotherapy alone was predictive of a low CD34+ yield in patients with NMM (regression coefficient (RC)=−2.1; P=0.003). In addition, the interactions “diagnosis mutliple myeloma (MM)×mobilization with chemotherapy” (RC=2.9; P=0.004) and “diagnosis MM×mobilization with chemotherapy plus G-CSF” (RC=2.1; P=0.04) also remained in the model, both showing a favorable influence. In AML, mobilization with chemotherapy plus G-CSF was associated with higher CD34+ yields (P=0.003). In this subgroup of patients, multiple regression analysis identified the number of cycles of previous chemotherapy (≤2 cycles; RC=1.3; P=0.03) and peripheral blood counts (WBC ≥1.5×109/l and monocytes >20%; RC=0.8; P=0.02) as the factors most predictive of CD34+ cell yield. These findings emphasize the need to optimize harvesting technique to enhance safety and minimize morbidity and costs of this valuable procedure.