The Absolute Number of Peripheral Blood CD34+ Cells Predicts a Timing for Apheresis and Progenitor Cell Yield in Patients with Hematologic Malignancies and Solid Tumors

Abstract

Retrospective analysis was conducted in 51 autologous peripheral blood progenitor cell (PBPC) collections using the Spectra AutoPBSC^TM System from patients with hematologic malignancies and solid tumors to study the predictive value of CD34+ cell counts in the peripheral blood for the yield of CD34+ cells in the apheresis product. The correlation coefficients for CD34+ cells μL⁻¹ of peripheral blood with CD34+ cell yield (×10⁶ kg⁻¹ of body weight and ×10⁵ kg⁻¹ of body weight L⁻¹ of blood processed) were 0.903 and 0.778 (n=51 collections), respectively. Products collected from patients with CD34+ cell counts below 15 μL⁻¹ in the peripheral blood contained a median of 0.49×10⁶ CD34+ cells kg⁻¹ (range: 0.05-2.55), whereas those with CD34+ cell counts more than 15 μL⁻¹ contained a median of 3.72×10⁶ CD34+ cells kg⁻¹ (range: 1.06-37.57). From these results, a number of at least 15 CD34+ cells μL⁻¹ in the peripheral blood ensured a minimum yield of 1×10⁶ CD34+ cells kg⁻¹ as obtained by a single apheresis procedure. The number of CD34+ cells in the peripheral blood can be used as a good predictor for timing of apheresis and estimating PBPC yield. With regard to our results, apheresis with a possibly poor efficiency should be avoided because the collection procedure is time-consuming and expensive.