Predictive factors for successful peripheral blood stem cell mobilization and collection in children

Factors affecting the success of peripheral blood stem cell collection (SCC) in children are not well characterized. We reviewed 218 stem cell collections among 199 pediatric donors, of which 35 were from healthy sibling donors and 164 were for autologous collections. Successful SCC, defined as a CD34⁺ cell count of ≥2 × 10⁶/kg of recipient weight per intended transplant, occurred in 188 of 199 donors (94%). Ideal SCC defined ≥5 × 10⁶ CD34⁺ cells/kg of recipient per intended transplant, occurred in 147 (74%) patients. Failure of collection occurred in 11 (6%) patients and was significantly associated with an autologous collection for a brain tumor diagnosis (P = .003) and a pre-apheresis peripheral blood (PB) CD34⁺ count <20 × 10⁶ cells/L (P = .002). Ideal SCC was significantly associated with age < 10 years (P = .01) and pre-apheresis PB-CD34⁺ count ≥20 × 10⁶ cells/L (P < .0001). Factors associated with failure of SCC may be identified in advance of the collection procedure allowing appropriate counselling of patients as well as anticipatory guidance for multiple collections or justify the preemptive use of stem cell mobilizing agents.