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 and Methods. The features of CD34+ cell mobilisation of patients with haematological malignancies that underwent autologous bone marrow transplantation were examined. Mobilisation chemotherapy consisted mainly of cyclophosphamide (CY) 4 or 7 g/m2 followed by growth factors. Leukapheresis was started when the WBC counts reached 1.0×109/l with the aim to collect at least 5×106 CD34+ cells/kg body weight. The aphereses were performed 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 lymphoma (NHL), 15 Hodgkin's disease (HD), two chronic myeloid leukaemia (CML) and three multiple myeloma (MM). Eleven patients could not collect the proposed threshold of CD34+ cells. CY 4 mobilised patients recovered WBC counts in less days (P=0.03). By ANOVA, the days to WBC recovery had a linear function of the predictors "number of aphereses" and "type of mobilisation CT" (coefficients: 0.86 and 0.95, respectively). For the number of aphereses and WBC recovery after CT mobilisation, we obtained a correlation coefficient of 0.36 (P=0.02). Conclusion. This study shows that it is feasible to mobilise and collect PBPC in patients previously treated with CT with or without RT. There was a linear correlation between the days for WBC recovery and the number of aphereses needed to collect the target number of CD34+ cells. The study suggests 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. © 2000 Elsevier Science Ltd. All rights reserved.23291100Kessinger, A., Armitage, J.O., Landmark, J.D., Autologous peripheral haematopoietic stem cell transplantation restores hematopoietic function following ablative therapy (1988) Blood, 71, pp. 723-727Williams, S.F., Bitran, J.D., Richards, J.M., Peripheral blood-derived stem cell collections for use in autologous transplantation after high-dose chemotherapy: An alternative approach (1990) Bone Marrow Transplant, 5, pp. 129-133Kessinger, A., Armitage, J.O., Smith, D.M., High-dose therapy and autologous peripheral blood stem cell transplantation for patients with lymphoma (1989) Blood, 74, pp. 1260-1264Dreyfus, F., Leblond, V., Belander, C., Peripheral blood stem cell collection and autografting in high risk lymphomas (1992) Bone Marrow Transplant, 10, pp. 409-413Santini, G., Congiu, A.M., Nati, S., Mobilisation/ transplantation of peripheral blood progenitor cells for aggressive non-Hodgkin's lymphoma with marrow involvement (1996) Leukaemia, 10, pp. S88-91Gianni, A.M., Siena, S., Bregni, M., High-dose sequential chemo-radiotherapy with peripheral blood progenitor cell support for relapsed or refractory Hodgkin's disease - A 6-year update (1993) Ann Oncol, 4, pp. 889-891Bierman, P.J., Vose, J.M., Armitage, J.O., Autologous transplantation for Hodgkin's disease: Coming of age (1994) Blood, 83, pp. 1161-1164Fermand, J.-P., Chevret, S., Ravaud, P., High-dose chemoradiotherapy and autologous blood stem cell transplantation in multiple myeloma: Results of a phase II trial involving 63 patients (1993) Blood, 82, pp. 2005-2009Marit, G., Faberes, C., Pico, J.L., Autologous peripheral-blood progenitor-cell support following high-dose chemotherapy of chemoradiotherapy in patients with high-risk multiple myeloma (1996) J Clin Oncol, 14, pp. 1306-1313Carella, A.M., Celesti, L., Lerma, E., Dejana, A., Frassoni, F., Stem cell mobilisation for autografting in chronic myeloid leukaemia (1997) Blood Rev, 11, pp. 154-159To, L.B., Haylock, D.N., Simmons, P.J., Juttner, C.A., The biology and clinical uses of blood stem cells (1997) Blood, 89, pp. 2233-2258Bensinger, W., Appelbaum, F., Rowley, S., Factors that influence collection and engraftment of autologous peripheral-blood stem cells (1995) J Clin Oncol, 13, pp. 2547-2555Tricot, G., Jagannath, S., Vesole, D.H., Peripheral blood stem cell transplants for multiple myeloma: Identification of favorable variables for rapid engraftment in 225 patients (1995) Blood, 85, pp. 588-596Kiss, J.E., Rybka, W.B., Winkelstein, A., Relationship of CD34+ cell dose to early and late hematopoiesis following autologous peripheral blood stem cell transplantation (1997) Bone Marrow Transplant, 19, pp. 303-310Tarella, C., Ferrero, D., Bregni, M., Peripheral blood expansion of early progenitor cells after high-dose cyclophosphamide and rhGM-CSF (1991) Eur J Cancer, 27, pp. 22-27Goldschimidt, H., Hegenbart, U., Haas, R., Hunstein, W., Mobilisation of peripheral blood progenitor cells with high-dose cyclophosphamide (4 or 7 g/m2) and granulocyte colony-stimulating factor in patients with multiple myeloma (1996) Bone Marrow Transplant, 17, pp. 691-697Ketterer, N., Salles, G., Moullet, I., Factors associated with successful mobilisation of peripheral blood progenitor cells in 200 patients with lymphoid malignancies (1998) Br J Haematol, 103, pp. 235-242Haas, R., Mohle, R., Fruhauf, S., Patient characteristics associated with successful mobilising and autografting of peripheral blood progenitor cells in malignant lymphoma (1994) Blood, 83, pp. 3787-3794Goldschmidt, H., Hegenbart, U., Wallmeier, M., Factors influencing collection of peripheral blood progenitor cells following high-dose cyclophosphamide and granulocyte colony-stimulating factor in patients with multiple myeloma (1997) Br J Haematol, 98, pp. 736-744Dreger, P., Klöss, M., Petersen, B., Autologous progenitor cell transplantation: Prior exposure to stem cell-toxic drugs determines yield and engraftment of peripheral blood progenitor cell but not of bone marrow grafts (1995) Blood, 86, pp. 3970-3978Kotasek, D., Shepherd, K.M., Sage, R.E., Factors affecting blood stem cell collections following high-dose cyclophosphamide mobilisation in lymphoma, myeloma and solid tumors (1992) Bone Marrow Transplant, 9, pp. 11-17Watts, M.J., Sullivan, A.M., Jamieson, E., Progenitor-cell mobilisation after low-dose cyclophosphamide and granulocyte colony-stimulating factor: An analysis of progenitor-cell quantity and quality and factors predicting for these parameters in 101 pretreated patients with malignant lymphoma (1997) J Clin Oncol, 15, pp. 535-546Schwella, N., Siegert, W., Beyer, J., Autografting with blood progenitor cells: Predictive value of preapheresis blood cell counts on progenitor cell harvest and correlation of the reinfused cell dose with hematopoietic reconstitution (1995) Ann Hematol, 71, pp. 227-234Remes, K., Mantinlauri, I., Grenman, S., Daily measurements of blood CD34+ cells after stem cell mobilisation predict stem cell yield and posttransplant hematopoietic recovery (1997) J Hematother, 6, pp. 13-19Smolowicz, A.G., Villman, K., Tidefelt, U., Large volume apheresis for the harvest of peripheral blood progenitor cells for autologous transplantation (1997) Transfusion, 37, pp. 188-192Ford, C.D., Pace, N., Lehman, C., Factors affecting the efficiency of collection of CD34- positive peripheral blood cells by a blood cell separator (1998) Transfusion, 38, pp. 1046-1050Santini, G., De Souza, C., Congiu, A.M., High-dose cyclophosphamide followed by autografting can improve the outcome of relapsed or resistant non-Hodgkin's lymphomas with involved or hypoplastic bone marrow (1999) Leuk Lymphoma, 33, pp. 321-330Velasquez, W.S., Cabanillas, F., Salvador, P., Effective salvage therapy for lymphoma with cisplatin in combination with high-dose ara-C and dexamethasone (DHAP) (1988) Blood, 71, pp. 117-122Carella, A.M., Frassoni, F., ICE, mini-ICE or high-dose hydroxyurea to mobilise Philadelphia [Ph]-negative PBPC in chronic myelogenous leukaemia (1996) Br J Haematol, 95, pp. 213-214Caracciolo, D., Gavarotti, P., Aglietta, M., High-dose sequential (HDS) chemotherapy with blood and marrow cell autograft as salvage treatment in very poor prognosis relapsed non-Hodgkin's lymphoma (1993) Bone Marrow Transplant, 12, pp. 621-625Sutherland, D.R., Keating, A., Nayar, R., Sensitive detection and enumeration of CD34+ cells in peripheral and cord blood by flow cytometry (1994) Exp Hematol, 22, pp. 1003-1110Armitage, P., Berry, G., (1994) Statistical Methods in Medical Research, 3rd Ed., , Oxford: Oxford University PressRao, C.R., (1995) Linear Models: Least Squares and Alternatives, p. 352. , New York: SpringerD'Arena, G., Musto, P., Di Mauro, L., Predictive parameters for mobilised peripheral blood CD34+ progenitor cell collection in patients with haematological malignancies (1998) Am J Haematol, 58, pp. 255-262Gandhi, M.K., Jestice, K., Scott, M.A., The minimum CD34 threshold depends on prior chemotherapy in autologous peripheral blood stem cell recipients (1999) Bone Marrow Transplant, 23, pp. 9-13Valbonesi, M., Hemopoietic stem cells: Technical and methodological considerations (1993) Stem Cells, OCTOBER 11 (3 SUPPL.), pp. 58-63To, L.B., Shepperd, K.M., Haylock, D.N., Single high-doses of cyclophosphamide enable the collection of high numbers of hemopoietic stem cells from the peripheral blood (1990) Exp Hematol, 18, pp. 442-447Rowlings, P.A., Bayly, J.L., Rawling, C.M., Juttner, C.A., Tokljklkl, L.B., A comparison of peripheral blood stem cell mobilisation after chemotherapy with cyclophosphamide as a single agent in doses of 4 or 7 g/m2 in patients with advanced cancer (1992) Aust N Z J Med, 22, pp. 660-664De Luca, E., Sheridan, W.P., Watson, D., Prior chemotherapy does not prevent effective mobilisation by G-CSF of peripheral blood progenitor cells (1992) Br J Cancer, 66, pp. 893-899Richman, C., Weiner, R., Yankee, R., Increase in circulating stem cell following chemotherapy in man (1976) Blood, 47, pp. 1031-1039Siena, S., Bregni, M., Brando, B., Circulation of CD34+ hematopoietic stem cells in the peripheral blood of high-dose cyclophosphamide treated patients: Enhancement by intravenous recombinant human granulocyte macrophage colony stimulating factor (1989) Blood, 74, pp. 1905-1914Haas, R., Hohaus, S., Egerer, G., Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) subsequent to chemotherapy improves collection of blood stem cells for autografting in patients not eligible for bone marrow harvest (1992) Bone Marrow Transplant, 9, pp. 459-465Boiron, J.M., Marit, G., Faberes, C., Collection of peripheral blood stem cells in multiple myeloma following single high-dose cyclophosphamide with and without recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) (1993) Bone Marrow Transplant, 12, pp. 49-55Peters, W.P., Rosner, G., Ross, M., Comparative effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) on priming peripheral blood progenitor cells for use with autologous bone marrow after high-dose chemotherapy (1993) Blood, 7, pp. 1709-1719Bolwell, B., Goormastic, M., Yanssens, T., Comparison of G-CSF with GM-CSF for mobilising peripheral blood progenitor cells and for enhancing marrow recovery after autologous bone marrow transplant (1994) Bone Marrow Transplant, 14, pp. 913-918Krause, D.S., Mechanic, S.A., Snyder, E.L., Mobilisation and collection of peripheral blood progenitor cells (1997) Apheresis: Principles and Practice, pp. 433-451. , McLeod BC, Price TH, editors. Bethesda, MD: AABB Press