Blood, 15 April 2001, Vol. 97, No. 8, pp. 2194-2194
G-CSF: early benefits but late risks?
Many oncologists are considering granulocyte colony-stimulating
factor (G-CSF) a drug of mainly benefits with only few and minor side
effects for patients with neutropenia following treatment with
myelosuppressive chemotherapy. In a retrospective study, Volpi and
colleagues (page 2514) describe significant long-term cellular immune
impairment of T cells in patients treated after HLA
haplotype-mismatched hematopoietic stem-cell transplantations with
G-CSF to reduce the period of neutropenia and improve engraftment after
transplantation. The benefits shortly after transplantation appeared to
be minor, whereas the long-term immune dysregulation may be
significant, as illustrated by the reduced capacity of T cells to cope
with fungal infections. Thus far, these findings could not be
translated into a significant difference in clinical outcome. The
authors also show that G-CSF treatment may have a negative influence on
the in vitro immune functions in normal donors treated with G-CSF to
mobilize stem cells for transplantation. This raises the question of
whether long-term immune functions have been sufficiently monitored in
these volunteers to conclude that G-CSF-induced mobilization of stem
cells is without significant health risks for the donor. Furthermore,
the use of G-CSF in many patients treated with relatively low doses of
chemotherapy resulting in only short-term neutropenia may have to be
reevaluated. Although the numbers of days of neutropenia or
hospitalization can be reduced, possible late cellular immune
dysfunction has not been addressed in most clinical studies. The report
by Volpi and colleagues indicates that the long-term immunologic
effects of G-CSF should be monitored and that new prospective
randomized studies may be necessary to allow a balanced assessment of
the short-term benefits against potential long-term risks.
J. H. Frederik Falkenburg
Leiden University Medical Center
