Abstract
background.
High dose therapy and autogenic or allogeneic stem cell transplantation plays an important role in the treatment course of hematological malignancies. In some countries, major method of unrelated stem cell donation programs had shifted from bone marrow harvest (BM) to peripheral blood stem cell harvest (PBSCH). PBSCH is a heavy duty not only for donor or patient, also for medical staffs. In some cases, poor mobilization may cause poor collection of stem cells. Hemogram needs time for May-Giemsa stain, and CD34 count needs complicated technique and running cost. New simple tool to predict the count of mobilized stem cell is needed to optimize PBSCH.
methods.
Since 2009, we started measuring peripheral blood hematopoietic progenitor cell (HPC) with Sysmex XE-5000(R) blood cell counter. With IMI channel method, we could rapidly know the count of circulating stem cells. Daily HPC count and yielded CD 34 positive cell count were analyzed.
results.
189 samples were collected from 122 donors/patients. Diagnosis of patients: malignant lymphoma (n=29), leukemia (3), multiple myeloma (74), amyloidosis (5), cryoglobulinemia (1). 10 healthy donors were also included. Age: 18-66, Sex: male 82/female 40. Mobilization regimen: G-CSF 57, chemo+G-CSF 74, G-CSF+plerixafor 1
HPC count (cells/ul) and collected CD34 positive cells (106cells/kg) had positive correlation. When HPC count was above 25/ul, collected CD34 positive cells were above 1x106/kg (positive predictive value: 80.9%). Number of PBSCH operation was 1.59 in average. We also show three cases in which HPC count was useful to make clinical decision of initiating PBSCH.
discussion.
HPC and CD34 had positive correlation, and HPC >25/ul seems to be appropriate cut-off to start PBSCH. With our former threshold of PBSCH (G-CSF day>4, WBC >3000/ul), 241 operations were to be planned. Including HPC count, we could reduce PBSCH operation to 204.
Hematopoietic progenitor cell count is rapid and inexpensive method. Within 5 minutes, mobilized stem cells can be measured, and it may be also useful in outpatient-based harvest settings.
Figure 1 Figure 1.
Disclosures
No relevant conflicts of interest to declare.
PB2344 EVALUATION OF THE PREDICTIVE VALUE OF HEMATOPOIETIC PROGENITOR CELL COUNT IN SYSMEX XN ANALYZERS FOR CD34+ STEM CELL MOBILIZATION IN PERIPHERAL BLOOD PREVIOUS TO THE APHERESIS
