Long-term safety of granulocyte colony-stimulating factor in normal donors: is it all clear?

INTRODUCTION: Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor that stimulates the proliferation and differentiation of neutrophil precursor cells. G-CSF-mobilized peripheral blood (PB) hematopoietic progenitor stem cells (HPSCs) collected by apheresis are being increasingly employed for allogeneic transplantation in patients with malignancies as an alternative to bone marrow (BM) transplant. Documenting the safety of G-CSF as a mobilizing agent for HPSC donation has long been a matter of importance for physicians, particularly when volunteer, unrelated adult donors are involved. AREAS COVERED: We review publications in the field with the goal of providing an overview of these approaches. EXPERT OPINION: Trials and international donor registries have not shown any long-term effects associated with G-CSF therapy and a threefold-or-greater increased risk of leukemia or other malignancies through PB HPSC donation can be excluded. Our conclusions are that the administration of G-CSF to healthy donors has a favorable long-term risk-benefit profile, although it is essential to encourage the enrolment of donors in carefully designed programs for follow-up monitoring.