Correlation between granulocyte/macrophage-colony-forming units and CD34⁺ cells in apheresis products from patients treated with different chemotherapy regimens and granulocyte-colony-stimulating factor to mobilize peripheral blood progenitor cells

Abstract

We examined the efficiency of disease-specific “standard” chemotherapies epirubicin, cyclophosphamide (EC); cyclophosphamide, vincristine, doxorubicin, etoposide, prednisolone (CHOEP); epirubicin, ifosfamide (EPI/IFOS) for peripheral blood progenitor cell (PBPC) mobilization in comparison to well-characterized mobilization protocols, i.e. etoposide, ifosfamide, cisplatin, epirubicin (VIPE) and dexamethasone, carmustine, etoposide, cytarabine, melphalan (DexaBEAM). Twenty-seven patients with various malignancies underwent 75 apheresis procedures for PBPC collection. Median cell yields from all 75 aphereses were 1.18 × 10⁵ mononuclear cells/kg [range (0.28–3.7) × 10⁸], 1.4 × 10⁵ granulocyte/macrophage-colony-forming units (CFU-GM)/kg [range (0.2–11) × 10⁵] and 3.3 × 10⁶ CD34⁺cells/kg [range (0.35–17.7) × 10⁶. CD34⁺/CD90⁺ cells could be mobilized by all mobilization regimens used. The difference observed in the mobilization of CD34⁺ cells was only of low significance when the mobilization regimens were compared, whereas the mobilizations of MNC and CFU-GM were significantly different between the groups. Breast cancer patients treated with the VIPE regimen (including pretreated women) had a significantly higher CFU-GM rate than patients treated with EC (P = 0.0005). Mobilized CD34⁺ PBPC were correlated with CFU-GM in all apheresis products. The linear correlation coefficients differed for the various mobilization groups: DexaBEAM (r=0.9, P < 0.0001), VIPE (r = 0.68, P = 0.0024), CHOEP (r = 0.52, P = 0.022), EPI/IFOS (r=0.34, P=0.11) and EC (r=0.23, P=0.2). We conclude that clonogenic assays can provide additional information about the autotransplant quality, particularly when alternative or new mobilization regimens are being investigated.