MOBILIZATION OF BLOOD PROGENITOR CELLS WITH IFOSFAMIDE AND ETOPOSIDE (VP-16) IN COMBINATION WITH RECOMBINANT HUMAN G-CSF (FILGRASTIM) IN PATIENTS WITH MALIGNANT-LYMPHOMAS OR SOLID TUMORS

The mobilisation characteristics of ifosfamide and etoposide followed by Granulocyte Colony-Stimulating Factor fGCSF, filgrastim) were analy sed in 17 patients with malignant lymphoma and 24 patients with solid tumours, with respect to the optimum time to harvest progenitor cells and to the yields of progenitor cells that could be achieved. In addit ion, we analysed patient characteristics which could influence the siz e of the progenitor cell harvest. Clinical parameters which were corre lated with the size of the circulating progenitor cells (CPC) harvests were: the dose of G-CSF, dose of ifosfamide, sex, age, diagnosis and extent of pretreatment. CPC were mobilised with 3 g/m2 (n=11) ol 4 g/m 2 (n=30) ifosfamide on day I and etoposide 100 mg/m2/day, on days 1-3 i.v., followed by daily s.c. injections with filgrastim 5 mu g/kg (n=2 6) ol 10 mu g/kg (n=15) from day 4. The maximal progenitor cell harves t was achieved on either day 12 ol day 13 after the start of the ifosf amide/etoposide course. The median number of leukaphereses necessary t o harvest the target quantity of 3 x 10(6) CD34+ cells/kg body, weight was I (range 1-9). Thirteen/41 (32%) of the patients did not achieve the target yield of 3 x 10(6) CD34+ cells/kg. By multivariate analysis , the dose of GCSF and prior irradiation were associated with the numb er of progenitor cells harvested, while all other parameters, induding the dose of if osfamide and number of previous chemotherapy courses, were not. Sixteen patients received two ol more mobilisation courses. Despite the fact that the same mobilisation schedule was used the prog enitor cell yields after the first mobilisation course did not predict the results after the subsequent mobilisation courses, indicating tha t unknown transient factors may significantly influence the CPC yield.