Peripheral Blood Stem-Cell Mobilization and Collection Practices in Pediatric Patients With CNS and Solid Tumors

PURPOSE High-dose chemotherapy followed by autologous stem-cell transplant is an essential component of treatment for pediatric patients with solid tumors. However, the optimal strategy for peripheral blood stem-cell (PBSC) mobilization and collection in pediatric patients is currently unclear. This study aimed to evaluate the effectiveness of different mobilization approaches and identify factors associated with successful PBSC mobilization and collection in pediatric patients. METHODS We conducted a single-institution retrospective review of patients age 0-18 years with CNS and extracranial solid tumors, undergoing PBSC mobilization and collection between January 2013 and December 2023. RESULTS This study included 109 pediatric patients with CNS or solid tumors who underwent 120 PBSC mobilizations and 185 apheresis sessions. The majority (98.2%) achieved the minimum PBSC dose required for therapy. Among mobilization strategies, granulocyte colony stimulating factor (G-CSF) alone had the highest success rate (96.6%), whereas G-CSF combined with chemotherapy produced the highest average PBSC yield. However, the mobilization strategy was not significantly associated with successful PBSC mobilization and collection. The preapheresis peripheral blood (PB) CD34 + cell count ( P < .0001) was the only significant factor linked to successful collection and strongly correlated with average PBSC yield ( r = 0.84) although 61.5% of patients with PB CD34 + counts <20 × 10 6 /L still had adequate PBSCs collected for the intended treatment course. CONCLUSION PBSC mobilization and collection in pediatric patients with CNS and solid tumor was highly successful at our institution regardless of the mobilization strategy. Mobilization with G-CSF combined with chemotherapy produces a significantly higher PBSC yield compared with other strategies, and successful PBSC collection can be achieved with a PB CD34 + cell count of <20 × 10 6 /L.