Early total white blood cell recovery is a predictor of low number of apheresis and good CD34(+) cell yield

Objective. We analysed peripheral blood progenitor cell (PBPC) mobilisation and collection in order to assess the main factors related to CD34(+) cell yields in patients affected by haematological malignancies. Patients find Methods. The features of CD34(+) cell mobilisation of patient s with haematological malignancies that underwent autologous bone marrow tr ansplantation were examined. Mobilisation chemotherapy consisted mainly of cyclophosphamide (CY) 4 or 7 g/m(2) followed by growth factors. Leukapheres is was started when the WBC counts reached 1.0x10(9)/1 with the aim to coll ect at least 5x10(6) CD34(+) cells/kg body weight. The aphereses were perfo rmed on continuous-flow blood cell separators. The analysed variables were: age, diagnosis, CT mobilisation regimen, type of growth factor, number of previous CT lines, prior radiotherapy, days for WBC recovery and number of aphereses procedures to achieve the target of CD34(+) cells. Results, There were 41 consecutive patients (26 M/15 F): 21 non-Hodgkin's l ymphoma (NHL), 15 Hodgkin's disease (HD), two chronic myeloid leukaemia (CM L) and three multiple myeloma (MM). Eleven patients could not collect the p roposed threshold of CD34(+) cells. CY 4 mobilised patients recovered WBC c ounts in less days (P=0.03). By ANOVA, the days to WBC recovery had a linea r function of the predictors "number of aphereses" and "type of mobilisatio n CT" (coefficients: 0.86 and 0.95, respectively). For the number of aphere ses and WBC recovery after CT mobilisation, we obtained a correlation coeff icient of 0.36 (P = 0.02). Conclusion. This study shows that it is feasible to mobilise and collect PB PC in patients previously treated with CT with or without RT. There was a l inear correlation between the days for WBC recovery and the number of apher eses needed to collect the target number of CD34(+) cells. The study sugges ts that early WBC recovery, using mainly CY 4 mobilisation chemotherapy, is an important predictor of a low number of aphereses to achieve a good CD34 (+) yield. (C) 2000 Elsevier Science Ltd. All rights reserved.