Mobilization of peripheral blood progenitor cells after induction chemotherapy (THP-doxorubicin-vinorelbine-cyclophosphamide-fluorouracil) and granulocyte colony-stimulating factor in breast cancer

In order to evaluate the mobilization of peripheral blood progenitor cells (PBPC) after an effective induction regimen in breast cancer, we performed a study on 15 breast cancer patients, Between January 1995 and June 1996, these patients received TNCF (THP-doxorubicin, vinorelbine, cyclophosphamide, fluorouracil for four days, every 21 days) with G-CSF support (5 mu g/kg for 10 days after chemotherapy) to reduce aplasia, This regimen is known to result in a complete pathological response in 30% of patients. Between two cycles of TNCF treatment, hematological recovery was observed. Progenitor cells (CFU-GM and CD34(+) cells) and mononuclear cells in DNA synthesis (MCDS) counts were performed daily, between the 12th and 17th postchemotherapy days (81 samples), The results showed a similarity for hematological recovery and PBPC mobilization kinetics depending on the number of treatment cycles. The three methods used for PBPC evaluation were well correlated (P < 0.01) with an optimal mean PBPC recruitment by the last day of G-CSF administration: respectively, 11 520 (1729-26 539) CFU-GM/ml of blood, 249 (14-1160) CD34(+) cells/mu l of blood and 211 (21-554) MCDS/mu l of blood. These results suggested that a daily injection of G-CSF after one or two TNCF cycles will produce an effective PBPC mobilization in comparison with currently used regimens.