Background: Hematopoietic growth factor support is routinely used after autologous stem cell transplantation. The optimal starting date of this growth factor support has not been established yet, but many engraftment studies now recommend the fifth day after stem cell infusion (Day 5).
Study design and methods: After switching the start date of granulocyte-colony-stimulating factor (G-CSF) support from the day of transplant (Day 0 group), to Day 5 after stem cell infusion (Day 5 group), the impression arose that there was an associated delay in engraftment of both white blood cells and platelets (PLTs). A retrospective analysis of two cohorts was performed with attention to engraftment variables and resource utilization.
Results: Patients in the Day 0 group recovered an absolute granulocyte count of more than 0.500 x 10(9) per L significantly earlier than patients in the Day 5 group (p < 0.001 in log-rank test; median difference, 1 day). Time to PLT recovery of more than 20 x 10(9) per L, without transfusion support, was not significantly different between the Day 0 and Day 5 groups (p = 0.16; medians of 10 and 12 days, respectively). Resource utilization, defined as number of red blood cell and PLT transfusions, days with fever or on intravenous antibiotics, days with mucositis, and length of hospital stay, were not significantly different between the two groups (p >or= 0.15 in each case). Total charges for the transplant episode were also not different between the two groups (p = 0.48).
Conclusion: Starting G-CSF support on the day of stem cell infusion, instead of on Day +5, leads to faster hematologic recovery without a significant impact on resource utilization.