Large-volume apheresis for the harvest of peripheral blood progenitor cells for autologous transplantation

BACKGROUND: The mobilization and harvest of a sufficient number of peripheral blood stem and progenitor cells for autologous transplantation is an important aspect of treatment in patients with certain hematologic and solid tumor diseases. The level of CD34+ cells in peripheral blood is often used as a predictor of successful harvest. STUDY DESIGN AND METHODS: A total of 129 apheresis procedures in 38 patients have been investigated retrospectively to evaluate the possibility to predict the outcome by other measures, such as total treated blood volume (TBV) during the apheresis. RESULTS: No significant correlation was observed between the level of CD34+ cells per kg of body weight in collected apheresis components and the TBV in all 129 apheresis procedures. However, analysis of results from 22 apheresis procedures with TBV > 16 L (large-volume apheresis) and with <10 x 10(3) CD34+ cells per mL in the peripheral blood found a correlation between TBV and the number of CD34+ cells per kg of body weight in the collected component (R(2) = 0.585, p = 0.005). In patients who underwent large-volume apheresis (>16 L) and who had <10 x 10(3) CD34+ cells per mt in their peripheral blood, the number of CD34+ cells in the apheresis component was not correlated with that in the peripheral blood prior to harvest (R(2) = 0.262, p = 0.1569). In the patients who underwent apheresis procedures with TBV <16 L and who had >20 x 10(3) CD34+ cells per mt in their peripheral blood, there was a correlation between the number of CD34+ cells in the component and the number of CD34+ cells in the peripheral blood (R(2) = 0.800, p = 0.0000). However, there was not a correlation in this group between the number of CD34+ cells in the component and the TBV. There were no significant differences in the content of CD34+/CD33+ and CD34+/HLA-DR+ cells in the collected components in the two groups. CONCLUSION: TBV appears to be critical for the collection of a sufficient number of progenitor cells in patients with <10 x 10(3) CD34+ cells per mL in peripheral blood.