TRANSPLANTATION AND CELLULAR ENGINEERING
Peripheral blood stem cell yield calculated using preapheresis absolute CD34+ cell count, peripheral blood volume processed, and donor body weight accurately predicts actual yield at multiple centers
- This research was supported in part by the National Natural Science Foundation of China No. 81270645 and No. 81270617) and the Priority Academic Program Development of Jiangsu Higher Education Institutions.
- Presented in part at the American Society of Hematology Meeting 2011.
Accurate prediction of stem cell yield is important for planning leukapheresis procedures. A formula has been published (Pierelli et al., Vox Sang 2006;91:126-34) to estimate the CD34+ dose collected on the first day of leukapheresis that was based on the preapheresis peripheral blood (PB) CD34+ counts, the blood volume processed, and the donor's weight. The aim of this study was to assess the predictive value of this formula.
Study Design and Methods
Data were retrospectively collected on 1126 consecutive PB stem cell harvests conducted at five institutions. Information on age, sex, diagnosis, weight, preapheresis absolute peripheral CD34+ count, total blood volume processed, and CD34+ cells harvested per kilogram of body weight on the first day of apheresis was collected.
Among donors at least 18 years old, Pearson's correlation coefficient (r) between actual yield (AY) and predicted yield (PY) was 0.76. To characterize this correlation, AY and PY were classified as being within the conventionally acceptable CD34+ doses (>2 × 106-5 × 106 cells/kg), below this range (≤2 × 106 cells/kg), or above it (>5 × 106 cells/kg). The positive predictive value (PPV) of PY was estimated considering the distribution of AY as the “gold standard.” PPV was relatively high for PY of more than 5 × 106 cells/kg (85%), moderate for PY of not more than 2 × 106 cells/kg (72%), and low for PY more than 2 × 106 to 5 × 106 cells/kg (56%). A consistent pattern was observed within institutions.
The formula of Pierelli et al. is associated with a PPV that is high, moderate, and relatively low for the corresponding predicted CD34+ doses.