Administration of post-autologous PBSCT rhG-CSF is associated with long-term low concentrations of bone marrow hematopoietic progenitor cells

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been widely used after autologous peripheral blood stem cell transplant (APBSCT) in an attempt to reduce the duration of neutropenia, but whether this trea tment has any influence on long-term engraftment remains unknown. We have r etrospectively analyzed data from breast cancer patients to compare post-AP BSCT rhG-CSF administration in terms of the short-term benefit and myeloid marrow regeneration after 1 year. Group A included 10 patients not treated with post-APBSCT rhG-CSF, while groups B and C comprised 15 and 13 patients treated with this drug from days +1 and +6, respectively. No differences a mong the three groups were found in age, diagnosis, previous chemo-radiothe rapy, CD34(+)/CD71(-) cell concentration in pre-transplant bone marrow (BM) , mobilization schedule, CD34(+) cell yield, conditioning regimen and post- transplant radiotherapy. Post-APBSCT rhG-CSF was shown to accelerate neutro phil recovery, but there were no significant differences in platelet recove ry, transfusion requirements, days of fever, antibiotic administration or i nhospital stay. With regard to BM hematopoietic precursors 1 year after APB SCT, significantly lower concentrations of total CD34(+) cells, committed C D34(+)/CD33(+) subsets, and more immature CD34(+)/CD71(-) cells were found in both groups B and C compared with patients not having received the cytok ine (group A). Thus, post-APBSCT rhc-CSF administration does not appear to beneficially affect procedure outcome, and might even impair long-term marr ow hematopoiesis.