Docetaxel effectively mobilizes peripheral blood CD34+ cells.

Area of Science:

• Hematology
• Oncology
• Stem Cell Transplantation

Background:

• Mobilization of peripheral blood progenitor cells (PBPCs) is crucial for high-dose therapy (HDT) and autologous stem cell transplantation.
• Docetaxel is a chemotherapy agent used in breast cancer treatment, and G-CSF (granulocyte-colony stimulating factor) is often used to stimulate blood cell production.

Purpose of the Study:

• To prospectively evaluate the efficiency of docetaxel plus G-CSF in mobilizing PBPCs for breast cancer patients undergoing HDT.
• To determine the optimal timing for apheresis collection after docetaxel administration to achieve target CD34+ cell yields.

Main Methods:

• Prospective evaluation of 26 breast cancer patients receiving docetaxel (100 mg/m2) followed by G-CSF (10 microg/kg daily).
• Monitoring of peripheral blood CD34+ cell counts to determine peak mobilization days and collection efficiency.
• Analysis of apheresis collection data, including total CD34+ cell yield and time to hematological recovery post-transplantation.

Main Results:

• The combination of docetaxel and G-CSF effectively mobilized PBPCs, with peak CD34+ cell counts observed on days 8 and 9.
• A median total CD34+ cell yield of 9.7 x 10(6)/kg was achieved, meeting the minimum target of >4.5 x 10(6)/kg in 22 out of 26 patients.
• Hematological recovery, including absolute neutrophil count and platelet levels, was observed within acceptable timeframes following HDT and PBPC transplantation.

Conclusions:

• Docetaxel with G-CSF is an effective regimen for mobilizing PBPCs in breast cancer patients, enabling successful subsequent high-dose therapy and transplantation.
• Apheresis collection should be initiated approximately 8 days after docetaxel administration to maximize CD34+ cell yield.
• This mobilization strategy supports repetitive high-dose therapy cycles, demonstrating its clinical utility in managing breast cancer.