ABSTRACT
To evaluate the effect of mobilization of peripheral blood stem cells (PBSC) with high dose cyclophosphamide combination chemotherapy and G-CSF in breast cancer patients, a new mobilization protocol was designed on the basis of standard combination chemotherapy regimen, in which the dose of cyclophosphamide was raised to 2 to 4 times, and G-CSF began to be used at the dose of 150 micro g twice everyday when white blood cell (WBC) decreased below 1.0 x 10(9)/L. PBSC collection was performed while WBC increased over 5.0 x 10(9)/L during bone marrow recovering. The PBSC mobilization protocol was completed in 10 patients, the median nadir of WBC was 0.8 (0.4 - 1.0) x 10(9)/L, the median time of PBSC collection was 2 (2 - 4), the median number of collected CD34(+) cells was 6.43 (1.99 - 8.75) x 10(6)/kg. The results showed that the protocol, high dose cyclophosphamide combination chemotherapy, was an optimal PBSC mobilization regimen in breast cancer patients.