SUCCESSFUL COLLECTION AND TRANSPLANTATION OF PERIPHERAL-BLOOD STEM-CELLS IN CANCER-PATIENTS USING LARGE-VOLUME LEUKAPHERESES

It was the aim of our study to determine the collection efficiency and yield of CD34+ cells in 88 cancer patients (pts, 44 males/44 females) who underwent 154 large-volume leukaphereses (LV-LPs). The diagnoses were as follows: 18 patients had Non-Hodgkin's lymphoma, 9 Hodgkin's d isease, 24 multiple myeloma, 6 acute leukemia, 27 breast cancer, and 4 patients had solid tumors of different types. During the course of LV -LPs, 20 liters (l) of blood were processed at a median flow-rate of 8 5 ml/min (CS 3000 Baxter) and 130 ml/min (COBB Spectra), respectively. Peripheral blood stem cells (PBSC) were collected following granulocy te colony-stimulating factor (G-CSF)supported cytotoxic chemotherapy. A 31% and 21% mean decrease in the platelet and white blood count was noted at the end of the LV-LPs when compared with the pre-leukapheresi s values. The aphereses were well tolerated without adverse effects. T he level of circulating CD34+ cells was closely related to the number of CD34+ cells contained in the respective leukapheresis product (R = 0.89, P < 0.001). Compared with 270 patients who underwent 838 regular 10 l LPs, the yield of CD34+ cells/kg was almost two-fold greater (4. 84 +/- 0.63 X 10(6) [Mean +/- SEM] vs. 2.60 +/- 0.16 X 10(6), P < 0.00 1). The antigenic profile of CD34+ cells was assessed in 54 separate p roducts collected on the occasion of 27 LV-LPs following the processin g of 10 l and 20 l, respectively. The intra-individual comparison incl uded differentiation- as well as lineage-associated markers (CD38, Thy -1, c-kit, CD33, CD45RA). No difference in the subset composition was observed between the first and second product, arguing against a prefe rential release of particular CD34+ cell subsets during the procedure. As shown by molecular biological or immunocytochemical examination, t he likelihood of harvesting malignant cells using large-volume apheres es was not increased in comparison with regular leukaphereses. Single harvests of greater than or equal to 2.5 X 10(6) CD34+ cells/kg could be obtained in 74% of the patients, compared with 52% in case of regul ar LPs. As the majority of patients were autografted with more than 2. 5 X 10(6) CD34+ cells/kg following high-dose therapy, hematological re covery in general was rapid and not related to the type of apheresis p roduct used. Considering patient comfort and savings in resource utili zation, large-volume leukaphereses have become the standard procedure for PBSC collection in our center. (C) 1996 Wiley-Liss, Inc.