Release of Peripheral Blood Progenitor Cells during Standard Dose Cyclophosphamide, Epidoxorubicin, 5-Fluorouracil Regimen plus Granulocyte Colony Stimulating Factor for Breast Cancer Therapy

Background. High dose chemotherapy with the support of peripheral blood progenitor cells (PBPC) is increasingly used in the treatment of solid tumors. Although the best method of PBPC mobilization is still under investigation, it should be optimized for different tumor types to obtain antitumor effect and mobilizing activity. The authors report these results in terms of the number of PBPC released and the time of maximum mobilization induced by standard dose cyclophosphamide, epidoxorubicin, 5-fluorouracil (CEF) (cyclophosphamide 600 mg/m2, epidoxorubicin 60 mg/mz, 5-fluorouracil600 mg/mz) plus granulocyte colony stimulating factor (GCSF) in patients with breast cancer. Methods. Peripheral blood progenitor cells were studied by clonogenic assay of granulocyte macrophage colony-forming units (CFU-GM), megakaryocyte colonyforming unit (CFU-Meg) and erythrocyte burst-forming unit (BFU-E) and by flow cytometric analysis of CD34+ cells in 12 patients with early breast cancer throughout three cycles of CEF chemotherapy plus G-CSY. Results. Colony assays and CD34+ cell determination