EFFECT OF DIFFERENT CHEMOTHERAPY REGIMENS ON PERIPHERAL-BLOOD STEM-CELL COLLECTIONS IN PATIENTS WITH BREAST-CANCER RECEIVING GRANULOCYTE-COLONY-STIMULATING FACTOR

Purpose: To evaluate the effects of chemotherapy regimens on periphera l-blood stem-cell (PBSC) yields in patients with breast cancer who rec eive granulocyte colony-stimulating factor (G-CSF). Patients and Metho ds: One hundred patients with breast cancer received cyclophosphamide 4 g/m(2) for dose (CY) (n = 10), CY and etoposide 600 mg/m(2) (CE) (n = 13), CE and cisplatin 105 mg/m(2) (CEP) in = 19), or CY and paclitax el 170 mg/m(2) (n = 58), followed by G-CSF. PBSC collections were init iated when the WBC count recovered to greater than 1 x 10(9)/L. A mult ivariate analysis was undertaken to evaluate the effects of different chemotherapy regimens and patient variables on PBSC collections as mea sured by the yield of CD34(+) cells. Results: The medians of average d aily CD34(+) cell yields for patients who received paclitaxel plus CY, CE, and CEP with G-CSF were 12.9, 11.03, and 5.37 x 10(6)/kg, respect ively, compared with 2.02 x 10(6)/kg in the reference group that recei ved CY with G-CSF (P = < .0001, .002, and .09, respectively). On first -day collections, patients who received paclitaxel plus CY, CE, and CE P with G-CSF yielded medians of 11.07, 8.09, and 3.52 x 10(6) CD34(+) cells/kg, respectively, compared with 0.90 x 10(6)/kg in the reference group that received CY with G-CSF (P = .0006, .02, and .09, respectiv ely), The number of previous cycles of chemotherapy, previous radiothe rapy, marrow involvement, and phase and stage of disease did not have statistically significant effects on CD34(+) cell yield. Conclusion: C ombination chemotherapy regimens were superior to single-agent CY for the mobilization of CD34(+) cells. (C) 1997 by American Society of Cli nical Oncology.