Ten-year follow-up of unrelated volunteer granulocyte donors who have received multiple cycles of granulocyte-colony-stimulating factor and dexamethasone.

Before the mid-1990s, granulocyte transfusion therapy was limited by the inadequate cell dose collected. A single subcutaneous administration of recombinant human granulocyte–colony-stimulating factor (G-CSF) in normal donors followed by leukapheresis 12 to 16 hours later harvested three times the number of functionally normal neutrophils compared with corticosteroid pretreatment;1 the addition of corticosteroids resulted in even higher donor neutrophil counts.2 In most studies, the granulocyte donors were family members of the patient; in a few centers, unrelated volunteer apheresis donors were recruited to undergo G-CSF and dexamethasone mobilization to donate granulocytes for patients.3 Some blood centers are reluctant to administer G-CSF to volunteers because of concerns regarding possible long-term toxicity. The short-term side effects of G-CSF such as bone pain, headache, and myalgia are well studied in standard mobilization regimens for peripheral blood stem cell (PBSC) collection. A single dose of G-CSF plus dexamethasone produces a similar side effect profile compared to G-CSF alone for granulocyte donors.4 At least two studies have reported on 2- to 4-year follow-up of related PBSC and granulocyte donors who received G-CSF.5,6 The potential long-term effects of repeated G-CSF stimulation in unrelated volunteer granulocyte donors have not been reported and form the basis for this study.