ABSTRACT
BACKGROUND: Autologous stem cell transplantation is a treatment modality for several diseases. Prediction of successful mobilization may be useful to optimize hematopoietic stem cell collection. STUDY DESIGN AND METHODS: This was a retrospective study with data from transplantation candidates between September 2015 and December 2021 being analyzed. The medical record of each patient was reviewed to mine mobilization information. The laboratory data analyzed were CD34+ cell enumeration and pre-collection peripheral blood cell count. The primary outcome, good mobilization, was defined as a CD34+ cell count ≥20/µL. RESULTS: This study included 807 patients. Increased patient weight, low mean corpuscular volume, high nucleated red blood cells, peripheral blood mononuclear cell and immature granulocyte counts were significantly associated with good mobilization. In addition, patients diagnosed with multiple myeloma were two times more likely to be good mobilizers than patients with lymphoma. The model was applied to a validation set to identify patients who underwent apheresis (CD34+ cell count ≥10 µL), resulting in a sensitivity of 69 %, a specificity of 95 %, positive predictive value of 98 %, and a negative predictive value of 50 %. CONCLUSION: Success in mobilization was greater in patients who underwent the first mobilization cycle and who had a diagnosis of multiple myeloma. Furthermore, higher body weight, and nucleated red blood cells, immature granulocytes and mononuclear cell counts, as well as low mean corpuscular volumes, were associated with successful mobilization.
ABSTRACT
BACKGROUND: The kinetics of hematopoietic recovery after autologous stem cell transplantation (ASCT) may be affected by laboratory procedures. The aim of this study was to evaluate the influence of characteristics of the cryopreserved units of peripheral blood stem cells (PBSC) on postthawing cell viability and engraftment outcomes after ASCT. STUDY DESIGN AND METHODS: This was a retrospective cohort study including individuals referred for ASCT. Cryopreservation was conducted at a single processing facility between 2014 and 2019, and patients received clinical care at six transplant centers. Covariates and outcome data were retrieved from participants' records. RESULTS: The study population comprised 619 patients (345 [55.7%] male). Median age was 53 years. Multiple myeloma was the most common diagnosis (62.7%). Higher preapheresis CD34+ cell count, lower nucleated cell (NC) concentration per cryobag, and composition of the cryoprotectant solution (5% dimethyl sulfoxide [DMSO] and 6% hydroxyethyl starch) were statistically significantly associated with higher postthawing cell viability. The linear regression model for time to neutrophil and platelet engraftment included the infused CD34+ cell dose and the composition of the cryoprotectant solution. Patients who had PBSC cryopreserved using 10% DMSO solution presented six times higher odds (odds ratio [OR] = 6.9; 95% confidence interval [CI]: 2.2-21.1; p = .001) of delayed neutrophil engraftment (>14 days) and two times higher odds (OR = 2.3, 95%CI: 1.4-3.7; p = .001) of prolonged hospitalization (>18 days). DISCUSSION: The study showed that mobilization efficacy, NC concentration, and the composition of the cryoprotectant solution significantly affected postthawing cell viability. In addition, the composition of the cryoprotectant solution significantly impacted engraftment outcomes and time of hospitalization after ASCT.
